Some will do a flat cost for a UDRP, others are by the hour (Typical $200 - $300 / hour, but there are those that charge more/less.). UDRP's can take a good deal of time depending on the complexity and issues.

Many will do do an initial consultation for free - just ask (Probably won't be giving away the keys to the castle in a free consultation, but could keep you from spending time and energy on a lost cause.).

John Berryhill http://www.johnberryhill.com/
Robert Cumbow http://www.grahamdunn.com/
Brett Fausett http://www.cckllp.com/
Jon Farnsworth http://www.felhaber.com/
Ari Goldberger http://www.esqwire.com/
Deborah A. Logan http://www.domainlegalcounsel.com/
Eric Menhart (Massachusetts) http://www.cyberlaw.pro/
Zak Muscovitch (Canada) http://www.DNattorney.com/
Jane Mutimear http://twobirds.com/English/Lawyers/Pages/Jane_Mutimear1.aspx
Stephen Lieberman http://www.aplegal.com/
Brett Lewis http://www.lewishand.com/
Howard Neu http://www.neulaw.com/
Derek Newman http://www.newmanlaw.com/
Enrico Schaefer (Michigan) http://www.traverselegal.com/
Neil Smith http://www.sheppardmullin.com/
David Steele (California) http://www.cph.com/
Steve Sturgeon http://www.domainnamedisputelawyers.com/
Adam Taylor http://www.adlexsolicitors.co.uk/
Brett Wakino (California) http://www.wakino.com/