Next Week : Friday-Feb. 21--Ventura...

If you haven’t bought that special Valentine gift yet--or even the Valentine, there’s still time to choose something special from among the sentimental treasures to be found at shows this weekend.

Riverside Antique Show and Sale opened Friday and runs through Sunday at Raincross Square Convention Center, Riverside. Dealers from coast to coast are at this show, offering all categories of antiques, many from Europe and the Orient. In addition to furniture, glass, china and porcelains, there’s jewelry. From tin to Tiffany is how the show is billed. The glass doctor is at the show fixing all types of glass, crystal or porcelain while show visitors shop. Admission is $3.50; hours today are 1-10 p.m. and Sunday noon-6 p.m. Free parking.

Ebell Antiques Show & Sale is in a very appropriate setting, the Ebell Club of Los Angeles, 4400 Wilshire Blvd., Los Angeles. The show opened Friday and runs through Sunday. Dealers represent an area from Kansas City to San Francisco. There will be an appraisal clinic that permits one free antique appraisal with each paid admission. Hours are noon to 9 p.m. today; noon to 5 p.m. Sunday. Admission is $4, and parking is free.

Something Old, Something Nouveau sale is today only at 1303 Lincoln Blvd., Santa Monica. Independent dealers display their wares on the lawn of this cottage. Hours are 9 a.m.-4 p.m. No admission fee. Information: (213) 395-8088.

Madame Z’s Doll Show and Sale is Sunday only at Rochelle’s Convention Center, 3333 Lakewood Blvd., Long Beach. More than 50 dealers will be exhibiting dolls from the turn of the century to the ‘80s. Admission is $2.50 for adults; children under 12 are admitted free and must be accompanied by an adult. Free parking.

Outdoor Discount Market is Sunday only at Long Beach Veterans Stadium, Lakewood Boulevard and Conant Street, Long Beach. Hours are 8 a.m.-3 p.m. Admission is $1.50; children under 12 free. Free parking.