Glad you are pleased with your purchase.
I use the Sigma 105mm lens and am happy with it. Generally gets good results. My only criticism of the lens is that the auto focus is clumsy. Can't comment on any other macro lenses as I've never used any others.
Other useful extras can include, tripod, flash, extension tubes for macro. The list is almost endless and it can get very expensive.
Here is a link for the sigma, but I may be worth shopping around or even considering agood second hand lens.
http://www.wilkinson.co.uk/sigma-ex-...o-for-eos.html