No I don't have any link to give you but I'm pretty sure you can just use the LOAD command in your BASIC programs to load PRG files to the addresses specified in their first two bytes with ie..
10 LOAD "BMDATA",8,1
20 LOAD "BMCOLRL1",8,1
30 LOAD "BMCOLRL2",8,1
I really don't want to get into the finer details of this here but using BASIC is likely to limit your freedom with where and how many images you could load, the data for one (full-screen) multi-colour mode bitmap is usually around 10KB and the BASIC and kernal ROMS occupy 8KB each, so that's 16KB gone before you even start.