There are a ton of post-bacc or summer fellowship programs for disadvantaged students (at least when I was in college several yrs ago). There should be a list on AAMC, but you can also check out sites for Student National Medical Association, schools themselves, or google. Be sure to talk to your premed advisor if you have one as well. I see that you're from Texas-- the UT system is sure to have programs for this. I know someone who did a summer fellowship for premeds at Texas A and M too.
Academic Medicine is a journal of the AAMC and you can look at pubmed for published studies done at different recruitment/post-bacc programs. It may give you some more information.
Good luck