A wheel would be like getting a whole new game. It did it for me, I was a mouser for years and got a G25.
It will not be enough to keep you interested, unless you are into hotlapping. You will have to actively look for places to drive. Find out what you want from online racing (winning, sprint races, endurance, fast switching combos, AS3 GTRs...) and then you will be able to select a few servers you like.
cargame.nl is ok for pickup races, combo switches often / track voting is on. There are not so many racers in each class though, and you can find anything driving standard wise (from learning the track by wall hitting to alien fast). There are also quite a few leagues around, and many "niche" servers.
LFS itself is not so important, the fun is in racing - for that you need decent physics, and good opposition. If you can spice that up with tactics (setup, pitstops) and adrenaline, you're good to go - but that could also be in RFact. or IRacin.
Good luck. And try a wheel