The company I work for has just been granted PSP license and we're still waiting for actual devkits to see what's the procedure regarding compilers etc. I'm not a programmer so I'm incapable to go into details.
But things I know for sure is that company that owns GLBasic (you have to be a company, private devs are a no-go) has to officialy apply for PSP license. Contact SCEE for specific details, as that is under NDA mainly. Contact SCEE for anything you need, they are very friendly towards devs.
Secondly, you cannot offer your "engine" or whatever to free purchase. You will need to have PSP product separated and sold ONLY to licensed PSP developers (companies, private devs are a NO-GO, again).
And as I said before, getting into PS licensed development is easy: you need few commercial titles (nothing too serious - flash, casual is perfectly fine) under your belt, proof of commercial status as a company and that's it. Easier than running Pizza delivery service!

That's for the upcoming PSP Go digital distribution service - Sony is trying to catch up with Apple so they are accepting more smaller developers. If you want to go into UMD distribution, that's a bit harder.