i'm trying to buy the bio textbook package used from someone but it appears every has already sold out of the latest edition. So I'm wondering if there are any major differences between last year's book.

I could have sworn I heard someone say that the last year's book was exactly the same except for some new diagrams or boxes or whatever.

Can anyone also back that up? I have bio 1m03 right now but I'm trying to look for a deal where I can get bio 1m03 and 1a03 textbooks as well as the how humans evolved crap and any other lil book that originally comes with it.

Last year's books are the exact same books as this year's. I think what you're asking about is the previous edition. The previous edition of Freeman's Biological Science is almost exactly the same as the most recent edition; the only difference is that the most recent edition has an included textbox every one or two chapters on "Canadian Research." These textboxes tend to be between half a page to one page in length. I believe only 2 of the textboxes were considered testable material.

TL;DR: Yeah, it's fine to buy the previous edition.