Does any know of a good, dependable place online to buy a good laser sight & mount for my AR?

Fulton Armory is a good place to buy.  Might not be the cheapest, but they are a good (reliable) place to buy.

Question is WHY would you want a laser???

why not? what would u get? a tac light?

Definately a Tac-Light.  It is a useful device.  A light can be used to illuminate a target (so you can ID it and/or shoot it).  Also the 'blinding' advantage of a decent tactical light is not to be discounted.

A laser is a toy.  CO2 lasers have their place with NVGs in Spec-Ops.  But the lasers that are commonly sold are cheap toys that offer no tactical advantage.  They can only be used in low light situations and they can't ID the target.  The dot is very difficult to see depending on clothes colors and distance to the target.

For night time shooting you are better off with a tritium front sight and/or a decent red-dot sight.  Personally I like red-dots as they work day or night and help you maintain situational awareness and speed up target engagement.

Quoted: why not? what would u get? a tac light?

OK boys, you say laser, he says tac-light.  Why don't you both buy a Insight Technologies M6 (multi-mode laser/tac-light), and the GG&G mount and be done with it. Tac-lights are practical and lasers are cool... it's a win/win situation.

Thank's forrest. I believe you're right.
Im gonna go with the tac light and tritium sight's.