EXS 24 Logic Sampler Users Group

As a beginner to this sampler game I am now looking at buying various 
sample CD's (thanks for the ethnic tips btw). Clearly not all are 
available in EXS format, so, which other formats are the easiest to 
convert / import or whatever? Excuse the ignorance, but I assume that 
if I get an audio format (wav, aiff or whatever) I would manually 
have do to all the mapping to the EXS? (or use the samples directly 
in the audio window)?

Are there any formats I should really avoid? (Samplecell, whatever 
that is, sounds like one!)

Thanks


Nic