In my story im writing, the main character is 'insane' and much of the storyline and plot are fueled by his schizophrenic experiences. Is there anywhere I can find descriptions of visions and halluciantions by real schizophrenics, or cases/accounts of them? (besides wikipedia)
First, the character is someone with schizophrenia, not "insane". Second, don't use Wiki for anything other than leads to real sources. There are many psychology/psychiatric sites online where, if you're honest with the admin, you can ask questions of members. I would also check with the local mental health groups in your area, such as NAAMI.
The Center Cannot Hold: My Journey through Madness by Elin Saks is a memoir written by a woman with schizophrenia, who is also a professor of psychology and of law. I have not yet read it, but want to, and I suspect it would be helpful to you.
google creatively and you will find more sources than you need... you can also find books about the subject with an amazon search...