As a resident of the Isle of man. Camping is generally the better option for experience also cheaper. You need to make a choice to how much of the racing you want to watch and where. How much time you want to spend out in nightlife will determine how close you want to stay to a town etc. Also what vehicle you bring to how much you want to enjoy the one way mountain section with no speed limit. But be aware it's similar to nurburgring but with alot more bikes and alot more public. Late night and early morning runs are most advised if you want a clear run.
Needs a fair amount of planning ahead as boat tickets sell out fast as do accommodation. Also on the watching front you can quite easily get stuck at one side of the island while watching for most the day with road closures. So pretty planning where to watch on what days etc goes a long way.
There are tones of Local BnBs and even more local rented rooms. Just check out some of the sites an they will point you in direction of registered public bed sits.
Is hard for me as a local to advise tourists coming over as living here I have never had to look into any of it Myself.
If you have any specific questions on locations, where you get stuck in etc, advice on what places are like then shoot me a Pm.
