So all indications seem to be that the Bills will bring in a another guard to bolster their offensive line. The Bills have seven healthy players including all 5 starters, but reserve center/guard Doug Legursky may be out for a while. The two reserves, Sam Young and Thomas Welch, are the primary backups but they play predominately at tackle (although Young did reps at guard as well). While it will take time to bring a free agent guard up to speed, there are some options to have active in a few weeks.
Here's a name a few may recognize...
Bobbie Williams [6-4, 345], most recently played as a backup for the Ravens in their super bowl run last year. Now the reason why he's still available is that he is 36 years old! Still the former second rounder has played in 164 games (136 as a starter) and has lasted around this long in the league. The Bills seem set with Colin Brown at LG so there is no pressure for a starter. At best, Williams won't have to play a snap given no injuries and a healthy return by Legursky. Until then, it couldn't hurt to have a vetted guard on the inside to act a viable backup; the Bills could then cut him if they wanted to when Legursky is back to 100%. At worse, you have a player on the O-Line that has been to a super bowl.
My thought is to sign him to a one year deal for around $600,000 to $750,000.