The desire to want to further our knowledge on these substances is appreciated! But dont get ahead of yourself, one step at the time.
To investigate and publish, when using a standard substance, they will have purchased it from the likes of sigma aldrich or other chemical supply companies, and this is mentioned in the paper. You cant use something you extract at home at least if you dont make sure its very pure using HPLC or such chromatographic techniques, because otherwise how can you know the effects you are seeing are really from pure DMT and not some impurity?
To purchase a substance like DMT legally to use in a research, you must imagine the bureaucratic work... You will have to be affiliated with some university or group with reputation that can ask for it in legal means. And everything is obviously controlled, you're not gonna store the DMT at home, it's all locked up in the university and so on. It can be done, but you need to know where to affiliate yourself. Or if your department has HPLC, you can purify your DMT with a preparative column and do your research and explain that your DMT was purified with HPLC. Rick Strasmann had extra trouble because he was gonna administer it to humans, so you cant just extract and purify, the source must have a lot of guarantees and Rick Strasmann was lucky to have Nichols do it for him. If you do In Vitro work or other things that dont require ingestion, you might get away with just asserting purification instead of source at least in some journals? Better check up more on this, your professor should know.
Then of course there is the issue of money, because any advanced serious research is gonna cost a lot, not only material but all the people involved. To get a research grant, you need to convince somebody with money your research is worth it, and unless you know some rich person with psychedelic interesting, it's not easy to convince the government or universities to give you these grants.
And then of course there's underground research.. Most dont get published, but lets say when somebody does a side-by-side extraction comparing a solvent versus other, or a temperature versus other, or a clean up versus other, these things are incredibly useful for the community to know, and yet there seem to be few of these tests around. If you get to develop your own extractions, you can always share the results and it will be very appreciated.
Keep us informed on your developments, whether official or not. Be well