i've recently insulated all my steam pipes in the basement with those fiberglass fittings w/self adhesive you can get at any of the big box stores. i didn't do any of the elbows though. do people recommend doing them and if so what can be used? thanks.

you can get roll insulation with a sticky side at the big box stores. It has a metal foil backing comes in 12 inch wide rolls. Simply cut into strips and wrap the ells.

You can get preformed fibreglass elbows from a plumbing supply house that have a light plastic cover that snaps into place. You'll need to know the pipe diameter. They are a much nicer looking installation than the wrap, albeit more expensive.

Here's another option. Look for a product called Hot Surface Coating 300. You can coat directly to the lines when the system is live. There is never any concern for condensation and rusting pipes plus the thermal control is more effective than standard insulations at only 100 mils thick. The added bonus is you can easily add more thickness whenever you desire more insulation.