First off I'm going to go with the cheap answer. A weedless Wooly Booger in the color to match your local crayfish.

Secondly, most crayfish patterns tied commercially do not use weedguards. If you are going to tie your own flies make sure that the weedguard won't ruin the action of the fly (If the fly is supposed to ride point up, but the mono weedguard is too heavy, your fly will ride point down.)
A fly that rides with the point up probably won't be too much help against weeds since you should fish your fly right on the lake floor. Remember that you may lose a few flies in this environment so don't tie a pattern that takes too much time.

( I spend too much time on alomst all my flies. How ironic that I usually fish the flies that were the fastest to tie!)

Warmouth

[This message has been edited by Warmouth (edited 08 August 2005).]