Okay so in The Tok'ra Parts 1 and 2 we are essentially introduced to the Tok'ra, or those 'Against Ra'.
We learn that their bases are underground complexes made by growing crystals superfast to form tunnels and other rooms depending on the tunnel used.
Thanks To Jacob Carter and the suggestion of using Sick Humans as Hosts, there is apparently an understanding or Alliance between the two groups.
What always got me was how oneside the Alliance was at times. On more than one occasion the Tok'ra would not help and Earth essentially let them use a beta site as a place to hide out.
The Tunnel technology I would of assumed would of least been shared with Earth, but outside of a few episodes we never saw it.
Im of the view that the alliance with the Tok'ra was VERY onesided.