How much recording time do I get with one charge of...

That depends on several factors. Power-hungry features like zoom, picture stabilization, and LCD viewscreens tend to decrease the amount of time between charges.
One nice feature of all newer camcorder batteries: they have no "memory" effect, so you don't have to run the battery down before recharging it. Some camcorders even interact with the battery to measure and display the remaining record time. Want to be sure you're not caught with a dead battery? Optional super-high-capacity batteries are available for many models, and a DC charger can be handy for recharging on the go.