Yeah, they can be very expensive.
The MPE65 is probably the "Macro Enthusiests" favorite macro lense, it's simply incredible (as it should be for over $800

)
You can even get the Tamron 28-75 2.8 macro (I have this lense, and it does 1:2 macro), slap on some kenko tubes an it works wonders.
Hell Ive even seen people put a full set of extention tubes onto the "NiftyFifty" (50mm 1.8) which sells for around $80 and get some amazing shots: some samples:
http://photography-on-the.net/forum/...d.php?t=148797
EDIT: Here's a link to the 28-75 2.8 lense I was talking about, sorry:
http://www.bhphotovideo.com/c/produc...2_8_XR_Di.html
I Love this lense.
Here are sample shots taken with it:
http://photography-on-the.net/forum/...d.php?t=145586
You can also see samples with that lense by going to my flickr site in my sig, then go to the cars and hockey folders. all shots in those were taken with this lense.
__________________
Mike Pics of my rig
HERE
Case:Lian Li with Swiftek apogee watercooling
CPU: Intel Q6600 (2.4 GHz)
Video: NVIDIA GeForce 8800GTX BFG OC Edition. LG 23" 1080HD and Sharp 19"
RAM/Storage:4GB Kingston Hyper X DDR2/320GB(7,200RPM) an 160GB(10,000 RPM) internals, and 320GB External
Sound Card: Creative X-Fi XtremeGamer Fatality
OS: Windows Vista Home Premium (64-bit)
M-B-Photos
Winner of Photo Tournaments:
Automobiles and
Birds