Beefing up the rear end?

I have a 97 Tacoma 2.4L 2wd, and i use it to pull my 2700lbs boat. It has plenty of power to pull it out of the water and down the street and even on the interstate. but my problem is that the back end of my truck is real sponge and when i hit bumps with the boat on the back it will stat to make the truck sway up and down and left to right. Is there anyway i can beef up the back end a little bit?

I think stronger shocks would be enough to solve your problem. Adjustables would be great - then you could soften them up for normal use and stiffen them for towing.

Do you know were i can get some airshock that will fit?

If you have lots of hitch weight on the truck your springs may need some type of overload spring or air lifts to get the rear of the truck to a normal ride height. A low riding height could upset the normal handling. The shocks on my new 2.4 two wheel drive Tacoma look like very low quality shocks. They have a soft ride but arent up to heavy duty work. If you have hi miles your shocks are probably worn out and need replacing. Upgradingthe shocks as Brian suggests would be a good starting point.

Clifton