So I'll soon be buying my first guitar; however the main problem I'm having is whether I should choose a left or a right handed guitar. I went into a guitar shop a few days back to have a feel on both a left handed and right handed guitar, and my first reaction even for the left handed guitar was to hold it right handed. However, the main concern is that I do everything (with the exception of a computer mouse) left handed, and even the air guitar test I did left handed. I'd love to be able to play right handed, as not only does it feel more comfortable, but it seems alot cheaper too . However, I'm concerned that when I can hopefully get to the level of playing challenging songs, my right handed strumming might let me down.

I'm looking forward to hearing your thoughts.

Lots of people find that the handedness they have in other things like writing doesn't necessarily transfer to guitar. The fine motor skills that you use for guitar are very far from anything else you're likely to have done, so most people can learn readily in either direction. My usual advice is that unless you show a really strong preference for left-handedness, you should probably learn righty. It makes things a lot easier, for all kinds of reasons. Tabs, available guitars, stage setups, etc are all simpler and easier if you aren't "backwards."

I doubt very much that you'll be hindered later on by choosing to play right-handed; after all, there's no real dominant hand in the guitar world, at least not across the board. Many very good guitarists are lefties who play right handed. You can trust your initial instincts on this one, I think.