check out this web site.. tcsd.org.lots of good info and very helpful links and free access to coaches,beginner to ironman...i joined the club and went from total couch potato to sprit tri in two months. it was tough.i did the back stroke on the swim! just keep swimming it will come,took me about 3 months of drinking pool water before i could freestyle.i am 46. didnt know how to swim.it is now fun for me and i dont drink much pool water now.
Yes a tri specific wet suit does make it easier to float! you still need all of the proper stroke that you learned in the pool though.Yes it does keep you warmHighly recomend for beginners for open water swimming.
Remember have fun! It will come.