can anyone recommend some books on filter design?

RF Circuit Design - C. Bowick

what kind of filter you want to design?
So we will recommend appropriate book for you.

EMI Filter Design - Ozenbaugh, ...

I remember there is a book named "mircostrip filter design"...

Run, don't walk, to the book store and order one of these:'
ISBN: 0890060991/ ISBN-13: 9780890060995
Microwave Filters, Impedance-Matching Networks, and Coupling Structures
(Hardcover)

by G Matthaei, Leo Young, E M T Jones


Rich