Mike,
Here's a pretty good page (with pics) detailing the process of replacing your oil seals.
http://www.yotatech.com/~corey/tech/...m1_oilseal.htm
It appears that oil seal failure is common on Tacomas as well as Tundras/Sequoias.
In my opinion, it's probably a good idea to replace the bearings at the same time. Bearings contaminated by gear oil will likely fail much quicker.