This is actually the part of the med school application process I'm dreading.  I graduated college in 2006, so I'm a non-trad.  I worked in pathology for about 5 to 6 years, dabbled in other career avenues, and became self-employed.  Exactly who I'm going to ask for LORs will be a huge conundrum.  I intend on going to my local community college down the block to complete my pre-reqs.  I've got an ultra competitive undergrad GPA, so it's a matter of just showing these schools that I can still perform well academically and obtain reasonable success on the MCAT.
But when it comes time to get LORs, I might have to get one from a client of mine, a volunteer supervisor at this homeless shelter I'm volunteering for, and perhaps an old supervisor of mine at a job I had about 5 years ago in a lab.  That's literally the best I can do.  Maybe I can get a community college science professor too.  Med schools will just have to understand that I'm in my mid-30s and a non-traditional applicant with more life experience under my belt than the traditional college student who jumps from course to course and doesn't take time to breathe.