coupling monitors to a stand

I used to have a set of Linn Kann mini monitors with metal framed stands. I made clamps by cutting a 1" thick bar of MDF that went across the top of the speaker, and another that went under the platform of the stand. I drilled holes near the ends of these bars, and used a length of threaded rod on each side, and some stop nuts and flat washers, to create a clamp that held the speaker to the stand. A little felt stopped any finish damage. This essentially made the speakers and stands a 1-piece unit. With good spikes on the bottoms of the stands, it was as good as you can get. Perfectly rigid. Didn't look like it was from a Design Studio though.

blu-tac
Its the stuff you use to mount posters etc to a wall

Cbirdl,
If you want to secure the speaker to the stand to help insure the speaker will not get knocked off you could implant three brass threaded inserts into the bottom of your speaker. Next drill corresponding holes in the speaker stand and bolt them together. You might want to put a thin piece of rubber type material between the two to prevent scratching.
The speakers would sound better if you used threaded audio points on the speaker and coupling disks on the speaker stand, however the speakers could be knocked off the speaker stand easily. The second suggestion is what I did to my monitors and stands to improve the performance of the speakers. See website at www.audiopoints.com

As above, Blu-tak or similar, available at most office supply stores. It will hold the speakers very securely, no worries about them getting knocked off, is an excellent coupler and damper, and is removable and reusable with no permanent damage to speaker or stands.