I would recommend swimming 2-3x/week though. If you can do 1500/workout try and get in some 200s and 300’s with 20-30sec rest between repeats. Concentrate on breathing bilateral and breathing every 1,2,3,4 and 5 strokes by 25’s on one repeat. Mix it up. This teaches controlling your breathing and creates a rhythm in your stroke. Then focus on DPS (distance per stroke) on other repeats by counting your strokes per 25 and reducing that stroke count throughout the 200 or 300.

The best video I’ve seen for freestyle (and there are vids for all strokes actually) is by David Marsh (Auburn head coach) featuring Rada Owen (’00 200 freestyle Olympian).

http://www.championshipproductions.com/cgi-bin/champ/p/Swimming-Diving/Swimming-Faster-Freestyle_MD-02210A.html

Also, Google "Swimming with Natalie Coughlin" She has a bunch of videos on Utube.

I’m a former Div I swimmer and a 1st yr masters swimmer, this will be my first year doing tri’s. I swim at St Peters college and Pershing Field pool in Jersey City. I teach private swim lessons on the side too.
References :

Get back to the pool and just get your ‘feel’ for the water back and your efficiency of form. If you train using 12 x 100M sprints (w/30 seconds Rest Interval) from now until race day (which becomes 3×200 + 6×100 —> 6×200 —> 3×400). On race day I’d think you should be out of the water in about 6-7 minutes.

Google Shinji Takeuchi on YouTube — he uses Total Immersion swim technique….
References :
Ironman.