Using wireless to get a fast connection where none exists

[Becker, Rob]

I have been trying to figure out how to get better than dial up access
to a location that has no DSL or cable available.  The location is
fairly high and probably has line of sight to areas that have DSL
available.  Is line of sight absolutely required to get a wireless
connection from one point to another?  I'm curious as to whether we
could get a connection using better antenna's etc from a site with DSL
to one without.  Does anyone have any experience with this?  What kind
of range can you get with Yagi antennas and the like?  What kind of
conditions are required for them to work?  Will a radio signal die off
if it hits trees, or just be weakened?  Any help appreciated.
Thanks.
Rob