If you're a member of the LTA I think they do package tours through Travelcare Sports in Manchester (inclusive tickets and Hotels). Personally I prefer to do my own thing though - there are loads of Hotels in Paris verging from luxurous 5 star to cheap B & B's and tickets are easy enough to get in advance. If you look through the Archives here you will find a thread from last year entitled something like "Roland Garros Useful Information". It will give you all the information you will need to know about travel, tickets, accomodation etc.
Supporting Djoković, Tipsarević, Soderling, Tursunov, Youzhny, Cilić and quite a few more