He's issued 10 albums during the past 13 years, is a regular at blues festivals small and large, and has cornered a nice niche performing on the blues cruises.

Yet to hear singer/guitarist Tommy Castro (in town Saturday night with the Legendary Rhythm and Blues Revue at House of Blues San Diego) tell it, he's still not sure exactly how he carved out a career in music.

"I never imagined I'd do it for a living -- it was something I did for fun," he said by cell phone while taking a cab ride in Las Vegas, where he was preparing for a show last week. "I wasn't in one of these families where everyone went off to college. We lived in a relatively low-income part of San Jose where everyone would grow up to get a job of some kind. And I figured that would probably be the thing for me. Music was the great escape. We'd get together with our friends, we'd have a great time, and I thought that would be the extent of it."

In fact, once out of high school, Castro took the exact route he described, taking a series of odd jobs.

"The main thing I did was I had my own small business installing window coverings. It was an easy thing to do because I could call my own hours and the money was good, but I didn't enjoy it that much. I liked the flexibility of that, being self-employed, and it allowed me to schedule occasional gigs during the week.

"I did some direct sales jobs and just scraping around, trying to find jobs to make a living, but none of it appealed to me.

"I hated everything I did for a living, and always kept the band going and playing weekends -- and it eventually dawned on me that this is what I was best suited to do."

It was his brother six years his elder joining a band that inspired Castro to pick up a guitar in the first place. Of course, it was his brother's guitar, and he could only pick it up when his brother wasn't home.

"I often wonder if I'd have thought to play music if it wasn't for him having guitars around," Castro said.

Self-taught with some pointers from his brother, Castro said he eventually tried a more formal music education but found it didn't stick.

"I took a few lessons, but I didn't do too well with that because I mostly play by ear and I'd already developed a lot of bad habits. I've always felt more comfortable with the way I play. Some of the lessons helped me a little bit, but for the most part I play by ear."

If his early music lessons were haphazard, no less so was his approach to finding a style of music to play.

"I didn't realize I was going to be doing this for a living; I was doing it for fun -- so I played what I liked," he said by way of explaining his immersion in the blues.

"I just gravitated toward the blues stuff. There was a lot of stuff going on when I was learning; it was the '60s. But the only stuff I was interested in playing was the R&B: Elvin Bishop, Paul Butterfield, the British blues guys. Taj Mahal was a big inspiration to me. B.B. and Albert (King) were playing the Filmore."

Involved in developing his current multi-artist tour, the Legendary Rhythm and Blues Revue, Castro said the format of the show is based on his experiences playing the blues cruises.

"Doing the blues cruises, I noticed that at night after everyone played their shows there was a jam session -- and it was the most amazing show of the night. Usually there would be a lot of people and a lot of different instruments and styles blended jamming up there together. It was just so fun for the players to do, and I would look at the crowd while this was going on and for blues fans it would seem to be the ultimate thing for them to watch. For some reason, you see someone do their regular show and it might be really great, but there's an element of the jam where nobody knows what's going to happen. Something really great and spontaneous and great could happen at any time.

"I thought, 'There's got to be some way to do this on land. We can bring the musical thing that happens there to miscellaneous venues around the country."

Joining Castro for the revue are Ronnie Baker Brooks (son of blues legend Lonnie Brooks), Deanna Bogart and Magic Dick (the harmonica player from the J. Geils Band). Each band plays a 20- to 30-minute set, and then, after a break, everyone comes out onstage together.

"We try not to have any plans for the jam that night; we come up and we jam like we do on the back deck of the (cruise) ship."

The Legendary Rhythm and Blues Revue with Tommy Castro, Deanna Bogart, Magic Dick and Ronnie Baker Brooks

When: 8 p.m. Oct. 20

Where: House of Blues San Diego, 1055 Fifth Ave., San Diego

Admission: $20-$40

Info: (619) 299-2583

Web: hob.com/venues/clubvenues/sandiego/ or tommycastro.com