Oh go on then...here I go?!?!?!?!?

Hi everyone.  

First ever posting on a forum...EVER!!  I am really wanting to do my first triathlon.  I have an entry for Tatton Triathlon Sprint distance (Manchester, UK) in September but I am no way fit enough to take part.  I am also hoping that if I can structure training it can help with weight loss.  I am 6'4" tall and 15st13lb (223lbs) and am hoping to get down to 15st5lb (215lbs)...I was 16st12lbs (236) one month ago.  

Have been in the gym every day for the last couple of weeks and following (very loosely) a weight watchers points programme).  Am a member of a Virgin Active Gym and they are doing a gym based triathlon in November (2.5km on the treadmill, 10km on the bike, 400m in the pool).  I did it last Thursday and got through it in 50mins38secs start to finish, including all transitions and a shower in between bike and pool...not getting into the pool that sweaty!!  

Anyway...now not a lurker.  Am looking for a training programme to follow if anyone has any details, tips, help, etc. etc etc.

David