The way I understand is is: Spot Toning: purposely increasing muscle in one area by working it (e.g. quads/obliques/lats) Spot Train: trying to lose weight in just one "problem area" (e.g. love handles) by exercising that area.
Obviously when you do cardio or strength training, you don't get to choose where those calories come off so it's impossible to spot train. But you want to keep your muscles in balance so if you found that swimming is increasing your bicep strength you might want to add a couple tricep exercises to your fitness routine to keep your muscles in balance. In that way you would be "Spot toning" your triceps.
Hope this helped!
P.S. you can definately get toned from swimming. The water provides excellent resistance.
I've seen my swimming friends tone up from just swimming. Keep trying it for a bit and see how it goes. If you see that you're not toning up as fast as you'd like, then maybe try some extra strength training on the side. Since your swimming already counts as cardio, you can pretty much strength train on whatever you feel needs work (legs, abs, arms, etc). Just my opinion.
I don't have any strength exercises in my plan because I hate it -.- But since I started swimming for the Summer swim team (around 2 weeks ago), it seems as though my arms have toned up a bit.. I mean, the muscles are definetly bigger.
So I know that it counts as cardio, but will this also tone me up some? Or do I really have to suck it up and start some strength training?