See:
http://www.hard-core-dx.com/nordicdx/antenna/feed/feed1.html
and
http://www.webex.net/~skywaves/ANTENNA/antsys.htm#4:1%20Balun
and
http://members.aol.com/WA1ION/nrants.pdf
the last one uses a MiniCircuits 9:1 tranformer that caosts about ~$5.
It has been several years since I bought one.

John Doty is very correct about the advantage of "TV" mathcing
cores over the more common 1" feritte cores. Pluse the TV cores
are cheap and still fairly pentifull.

Terry