Further notes on preparation:
The above recipe is perfect for the over-the-counter chemist on all points except one, the necessary component of petroleum ether, also known as naphtha. Going to Wal-Mart and asking for this will generate at best confusion, and at worst suspicion and a call for the rent-a-cops to escort you from the store. Most large hardware stores have seen enough wannabe methamphetamine chemists that they know not to trust people who are searching for a particular chemical, and in many cases a procedure for dealing with such people is taught to employees. So instead of asking, you should enter the store knowing exactly what you're looking for: Ronsonol Lighter Fluid, Zippo Lighter Fluid, Coleman Lantern Fuel, and generic versions of these. Lighter fluid will be kept behind glass with the cigarettes, and lantern fuel should be back with the camping supplies. Make perfectly sure what you're getting is a fluid and not an aerosol or pressurized gas -- it should slosh when you shake the container.
Unfortunately, there aren't any regulations regarding the labeling of these fluids, so they may contain all kinds of non-volatile compounds which will poison the end product of the extraction. Before doing any of the above steps, the "petroleum ether" in question should be tested for purity by filling a small dish, and leaving it outside to evaporate. If any solid, liquid, or gunk is left behind after the rest evaporates, whatever product you have bought is unsuitable for the extraction and should not be used for it under any circumstances.
Given that the solvent passes this litmus test, go ahead and use it for the extraction up to the step where it says "Dry the seed powder THOROUGHLY." To make sure the powder is completely solvent-free, stir it up and let it dry further a couple of times even after it looks dry. When you are convinced that everything that's going to evaporate has done so, give the powder a sniff. If it has any smell, chemical, perfumed, or otherwise, throw the seed powder away -- no matter how little residue is present or what its chemical nature is, it's not worth risking your health to find out whether or not it is safe for consumption. However, if the powder has no smell and isn't sticky, you can assume that whatever product you're using is relatively pure naphtha, and further that you should stock up on it while you can. For reference, I've used Ronsonol Lighter Fluid successfully in the past, but you should do the tests anyway; the DEA may force them to change their formula at any point, and possible ingestion of toxic chemicals is not something to fuck around with.
Also, if you're willing to perform a tactical vomit at two or three hours after ingestion, the non-polar purification step (i.e. the step using petroleum ether) is not strictly necessary. While the elements removed by this step cause nausea and stomach cramps, they cause no long-term damage to your body, and thus don't have to be avoided as rigorously as, say, petroleum additives. I have used an extraction which skipped the non-polar stage, and it made me violently, violently ill due to my body's reluctance to vomit given any lesser degree of stimulus. However, if you're the type who can throw up at the drop of a hat, as it were, forcing yourself to do so after the LSA has entered your bloodstream but before the seeds have made you sick may be the best option of all. You can bet that the aboriginal Middle Americans who discovered this plant's psychedelic properties didn't use a non-polar extraction stage....
On the use of this extract:
First, if you enjoy psychedelics only because of the light-show visuals that often accompany them, morning glory LSA extract is probably not the drug for you. Even at peak time with a high dose (roughly 350 Heavenly Blue seeds), I had virtually zero visual activity, eyes open or closed. The closest thing to visual activity was a dramatic sharpening of visual acuity, along with some very, very slight movement of objects viewed at a distance. Toward the end of the high-dosage trip there were some very simple geometric patterns in carpet and with closed eyes, but nothing remotely approaching the light-cycling-mandalas of LSD. With lower doses, even these signs weren't present.
As an aside, the lack of visual activity can be something of a benefit for the open-minded tripper. On most psychedelic drugs -- and make no mistake, even without visuals the morning glory extract is intensely psychedelic -- the visuals can interfere almost completely with reading and writing. With this substance, though, the visuals aren't a problem, so paper and computer text is as readable as your state of mind will allow, and writing with ink and paper becomes possible as well.
Also, trips from the extractions I've tried have been powerfully, overwhelmingly emotionally positive. In contrast to psilocybin and LSD, which let you use the whole emotional gamut including profound fear and sadness, morning glory extract seems to filter out those negative ones and leave you a grinning idiot for the duration. While this is great from a recreational point of view, it leaves something to be desired if you're trying to experience introspective or spiritual psychedelic effects. In this way the extract is almost like using marijuana -- it's easy to giggle about stupid shit, but difficult to accomplish anything concrete.
As with any psychedelic substance, don't take any person's experience with them as gospel. Depending on the variety of seeds used, the quality of extraction, and your state of mind during use, the effects can and probably will be completely different.