Christina Aguilera [ tickets ]'s first headlining tour will be an 11-week, 37-city endeavor that gets underway on July 31 and generally will visit 3,000- to 5,000-seat venues, according to a tour publicist. Although cities and dates for many of the tour's stops won't be announced until later this month, several stops and ticket on-sale dates have been confirmed.

The remainder of the teen pop star's itinerary will be released later this month and tickets will go on sale April 29.

While Aguilera has performed during fairs and radio festivals and as a supporting act on other tours, she hasn't previously been a headliner for a full-blown tour, according to the spokesperson. The summer/fall jaunt will be jointly sponsored by Sears and Levi's, and will be tied into marketing efforts by both companies.

Aguilera is booked to play some warm-up dates for the tour, which are already emerging as hot tickets on the fair circuit. According to her official website, the 10,000 tickets to July 28's MontanaFair appearance in Billings sold out in two hours. (Aguilera's live performance career path closely resembles the path taken by fellow teen pop star Britney Spears, who played the mall fair circuit before emerging as a headliner.)

Among the 19-year-old pop star's other pre-tour warm-up concerts is an hour-long May 19 appearance at the Tulip Festival in Holland, Mich.

Aguilera, who picked up the Best New Artist award at the 2000 Grammys, is promoting her eponymous first album, still in the Billboard Top 20 eight months after its release. The album spawned the hit singles ''Genie in a Bottle'' and ''What a Girl Wants,'' the latter of which is currently at No. 30 on the Billboard Hot 100. Her latest single, ''I Turn to You,'' debuted this week at No. 50 on the Hot 100.

Aguilera is scheduled to release a Spanish language album in September, and she is expected to complete a Christmas album in time for a November release. She isn't expected to record a follow-up to her 6-million-selling debut album until 2001.

(Holly Glasen, music editor of sacramento.citysearch.com, contributed to this report.)