Could you describe what they actually look like. "look infected" doesn't say much. If it is a toenail fungus, it could be spread from toe to toe or finger with your clippers. If you only have two nails infected (and it really is a toenail fungus) there are some home remedies that are supposed to work well. If it spreads to all of your toes, it will be hard to treat without getting a prescription for lamisil (very expensive stuff). Most of the home remedies involve vick's vaporrub by itself or after a soak in vinegar (don't know for how long though). Until you know whats going on for sure, isolate the affected nails... ie, don't use your nail clippers on those nails and then on the nonaffected nails. Fingernail infections are much rarer, and I would imagine that is both because your feet or always in a more humid enviroment, and don't get the same amount of constant washing etc. that the hands do. just a guess though.
Most if not all of the OTC fungus treatments do not work on nail fungus.
Also, any nail treatment that does work will still take a few months to show, so don't expect immediate results (however if successful you will be avoiding further infection of other nails during that whole time).