The American Idol finale won’t be the last time Alex Preston gets together with Jason Mraz. Preston, the third-place finisher who will sing with his musical hero on the season’s final episode next week, says Mraz has approached him about writing songs together.

“Jason wants to write, so we’re going to get something together,” Preston says. A few other people, including Michael Natter, who co-wrote Mraz’s I Won’t Give Up, and his wife, Nancy, have expressed interested in writing with Preston. “I’m really excited about it,” he says.

A day after his elimination from Idol, the singer/songwriter from New Hampshire is keeping an upbeat attitude, despite being the last person ousted before the finale. “I enjoyed it completely,” says Preston, 21, about his run. “I didn’t expect to get past the auditions. The fact that I made it to the top three out of 100,000 or whatever was pretty awesome. I’m happy about it.”

When Idol introduced Preston early in the year, he was presented as something of a multi-instrumentalist whiz kid. By this week, though, he’d locked into the role of quirky singer/songwriter so effectively that judge Harry Connick Jr. wondered how he’d stretch out in a concert setting. Preston told him about the “six-minute jams” at his homecoming show, and the few seconds of performance footage from that concert shown Thursday suggest viewers got to see only a part of what Preston believes he has to offer.

“When I do live shows, since I’m not going to be judged or in a competition, I’m excited to experiment with new instruments, take guitar solos and just jam, play long songs and fun songs,” he says. “I’m really excited to start the creative path and especially to record an album.”

Idol can sometimes push young performers into roles in which they’re not comfortable, like it did this season when trying to turn Sam Woolf into a teen heartthrob. Preston, though, says he was determined to use the advice of the mentors on the show to become…