Just inspect the crank pulley. That may explain why both power steering and alternator are being effected. You should be able to sort of see it in the wheel well if you turn your steering wheel to the left.
If all is good just replace the belts again. If you smoked one belt clean the pulleys off. Very important!
You could have had a bad belt and when you installed the alternator it required a heavy pull to charge the battery. Belt probably just couldn't take the stress. Especially on a wet day. I have one on my car that needs to be replaced.
To change the pulley...
Take all belts (or what is left of them...) off and there are 4 bolts that hold it on. You put the car in gear so that the crank doesn't move. you will have to remove the tire and some plastic guards. After that you should see the pulley well enough for inspection.
Here is a link to what it would look like...
http://www.dsmtuners.com/forums/showthread.php?t=169254