I'll add a little to what mpp said:
The OAT sections are:
Reading Comprehension
Qualitative Analysis (speed math)
Physics
O-chem
Gen Chem
Biological Science
It's scored on a scale from 200-400 with 300 being average.
Each school does require a seperate application. All require at least THREE letters of recommendation. Some require all three to be from PROFESSORS (like UHCO) which was really hard for people like me who've been out of school three years. I also sent in letters from OD's (always good to have an OD in there), and maybe someone from a volunteer oganization that you worked for. I also got one from a former employer at the biotech. company I worked for.
All the schools also require written essays in their applications. Some require two.. others require three. They're usually all different too, but I could cut and paste some essays into new ones for the three schools I did. (this was the most annoying part of the application process after the OAT)
Some schools accept on rolling admission and some don't. APPLY EARLY!! This is the same as medical school. Like mpp said some ppl will get interviews before their OAT scores come in. (they'll just hold your acceptance for scores)
Interviews in my opinion were a very relaxed part of the whole process. Some schools interview for an hour (SCCO did) and some 30 minutes (berkeley and UHCO). All three schools I interviewed at had one student and one professor interviewing. They generally just want to make sure you can communicate effectively.
After the interview most schools will make you do a written essay ON SITE! I think this serves two purposes. making sure you wrote your own essays.. and making sure you communicate effectively in english.
Well, that's all I have to say about that. feel free to ask more specific questions if ya got 'em.