LINCOLN THEATREIt was fascinating to watch Thad Cockrell transform himself into a recording artist by knocking on doors to hand out homemade CDs, by grabbing stage time wherever he could, and, it seemed, by sheer force of will. The two Triangle-recorded albums that resulted had honky-tonk hearts and a country-soul voice and earned alt-country accolades. We’re still waiting for his third solo album so we can gauge how his Nashville address is treating him, but his post-move duets album with Caitlin Cary, Begonias, was a sure beauty. Maybe tonight allows for backstage counseling: Young, country-conscious rockers American Aquarium seem to be on a similar career track. Tickets are $8-$10 for the 9 p.m. show. Rick Cornell