Weeping tile and a sump pump are usually the first calls to arms here... if it's coming up from the slab, then maybe your weeping tile is plugged or has some other issue.
As for water on a carpet - just so happens my first job (as soon as I could pass for 16 - when I was 12 or so) was working with my dad and his carpet cleaning business. For clean water, just get the carpet and underlay as dry as possible, it dries without mold very well by itself (after all, steam extraction cleaning leaves it wet, too)...
You may end up with a water mark where the puddle was... or a slight... not musty, but that kind of smell. Water marks can be cleaned by hiring a carpet cleaner to come out and do the carpet, and the best offense against the smell is any of the N*Odor products (Nilodor, N'Odor, etc)... failing that, Febreze is actually a pretty good (if more "consumer") backup.
The main problem is getting the water out of the underlay... the big commercial
vacs we used did it no problem, but they also looked like a taller version of R2D2. With a shop vac, take any attachments off, and use the end of the hose perpendicular to the carpet and suck the living hell out of it... it's got to pull that water up through the carpet backing and carpet yarn from the underlay.
Bren R.
