Even if you're a music fanatic, chances are you hadn't heard of Selena until a fan shot her to death on March 31 in Texas. Selena Quintanilla-Perez sang Tejano the contemporary offshoot of conjunto, a century-old blend of German dance music (played on accordions) and Mexican folk melodies. Spanish for ''Texan,'' Tejano is enormously popular in the Southwest, and major record labels like Sony and EMI annually churn out a slew of these albums; even cheese king K-tel took the plunge this year (see sidebar). Still, Tejano artists never cross over into the world of MTV. The genre is so ghettoized that it makes the new wave of gay punk rock seem downright mainstream.
Selena, who was only 23 and had sold almost 3 million records worldwide, was on the verge of changing that situation when she was murdered. At the time, she was in the process of recording her first English-language album for SBK, the label that brought us Jon Secada and Wilson Phillips. But listening to the four Selena albums (all on EMI Latin) that vaulted onto the pop charts in the wake of her death, it's clear she was more than just a bustier-clad ''Tex-Mex Madonna.'' With its trembling, tear-in-the-throb sob, her husky voice was rooted in both early-period Madonna and conjunto balladeering, and her songs were steeped in the same tales of unrequited passion that play such a large part in Latin music. (''What does it matter what your parents will say?/The only thing here is our love,'' she sings in ''Amor Prohibido'' [''Forbidden Love''].) Beneath the glitz and chirpy synthesizers was the last thing one might expect a living, breathing folk tradition.
For newcomers, the best introduction to Selena is the 1994 compilation 12 SUPER EXITOS. Songs like ''No Quiero Saber'' (''I Don't Want to Know''), which has the sweeping breadth of an Abba single, are unabashedly pop. But Selena never strayed from her roots. At least half of the album showcases her conjunto side: Check out ''Si Una Vez'' (''Maybe One Time''), which, with its mariachi horns and Selena's own full-throated warbling, recalls Lydia Mendoza, conjunto's leading lady. Unlike the nauseatingly kitschy mini-trend of Gen X lounge pop, this is music for a young audience that doesn't snicker at the sight of a squeezebox it's just another instrument to propel them onto the dance floor.
Selena's last album until the inevitable commemorative anthologies, that is was AMOR PROHIBIDO (1994). Produced by her brother, A.B. Quintanilla III, who also cowrote many of her songs, it stands as her sleekest and most pop-oriented work, as heard in peppy ditties like ''Bidi Bidi Bom Bom'' and a version of the Pretenders' ''Back on the Chain Gang,'' retitled ''Fotos y Recuerdos'' (''Photographs and Memories''). Never a virtuosic singer, Selena was at her most vocally confident here, even unleashing a guttural growl on an otherwise malnourished attempt at dance pop, ''Techno Cumbia.'' And as usual, she didn't forget her folk side; accordions and oompah beats are sprinkled throughout the record. An earlier, more tentative potpourri of both modern and traditional styles, ENTRE A MI MUNDO (1992) alternates between blatant attempts at crossover (her first English ballad, ''Missing My Baby'') and conjunto-minded originals like ''Qué Creias'' (''What Did You Believe?''), which Selena belts out with the fervent lust of someone who's downed a whole jar of hot sauce.