Sure, a mouse might work better or more precise, I just think that a joystick feels better in games like this. Especially considering the "lifting mouse" problem.
Way back I had a trackball instead of a mouse, which actually worked pretty well, too.

Saitek X-52. Not too expensive, GREAT, responsive throttle and stick, lots of buttons, great feel, works wonderfully in Freespace 2.

I totally agree with Veloxi, although It all really depends on your definition "not too expensive". For a space and flight sim enthusiast like myself, spending around a hundred pounds on a joystick can be justified. For the more casual gamer however, I would recommend something a little less extravagant; maybe the saitek cyborg or similar will be right up your street. Just make sure whatever joystick you do get has at least a throttle, a twist stick (or rudder pedals) and a hat and it should be more then adequate for freespace, and pretty much any other sim on the market.

Logitech make some damn fine sticks. Check them out:
http://www.logitech.com/index.cfm/gaming/pc_gaming/joysticks/&cl=gb,en

Regarding the Saitek joysticks - how durable are they? Back when I was spending most of my time playing the Wing Commanders and Descents to death, I broke my fair share of joysticks that simply weren't built well enough.
I had found a joystick that lasted me for a good while - I think it was a sidewinder, and cost about $45 at the time - but broke it years ago and haven't had need for one since.

It really is too bad Microsoft got out of the joystick business, I had a few until I got the Sidewinder Precision 2 and it's lasted me about 8 years now,. The USB plug got under one of the wheels on my chair and got itself crushed but I bent it back with needlenose pliers and now it works fine.

Have to second this. I just got the X52 Joystick & Throttle set... It's fantastic. Cost a fair bit but it's actually improved my Freespace game...The amount of control the throttle gives you in incredible... And it looks sexy as all hell :)
Karl

Another hearty agreement on how useful a throttle is. You can do a LOT more things a lot quicker when you have a programmable throttle handy. You can even program rudder controls onto most of them. I really love them for quick and instinctual weapons changes. Really improves your game a LOT.