getting ready for 2005

I am 40 years hold even if I always been active ( running , football ,rugby ) I was getting out of shape and my motivation was decreasing. I restarted to run and work out seriousely in march 2003 , then running in local races (from 5K to marathon ) at least once a month .I ran my first marathon last may in Buffalo ,NY and I loved it ,even the last 5miles where I had terribles cramps IN both harmstrings. Then I remembered my only triathlon I ran back in 1986 and the wonderfull experience it was . I just restarted to swimm and bike ( on a montain bike waiting to buy a decent triathlon bike ) and I am realy exited at the idea to tri a couple triathlon next year . I am open at any kind of advice.