Youth Basketball Registration Set

The Eastern Prince William Sports Club Basketball Division sign-ups will be held from 7 to 9 p.m. each Tuesday and from 4 to 6 p.m. Saturdays through Oct. 27 at the Sports Club on Longview Drive in Woodbridge. There are four leagues: coed instructional for ages 6 through 9, novice for girls 10 through 12, junior for girls 13 through 16 and ladies ages 17 and up. The cost is $25 a person, $40 for two and $55 for three. Call 680-2231, 680-2830 or 670-6019 for information. Business Group Forms

A networking organization for Prince William County and Manassas businesswomen is forming. Call Stephanie Williams at 369-0888 for details. Writers' Event Set

The Prince William Library will sponsor the Potomac Library's Second Annual Writers' Series at 7:30 p.m. Wednesday at the Potomac Branch. Larry Bond, author of "Red Phoenix," will be the guest speaker and will discuss his work as a writer. Pre-registration is required and may be done by calling 494-8126 or stopping by the library. Markets Stay Open

The Prince William County and Manassas farmers' markets will continue to display their goods each week until Oct. 28 and Nov. 1, respectively. The Prince William market sets up in the commuter lot at Dale Boulevard and Minnieville Road from 9 a.m. to 1 p.m. Sundays. The Manassas market operates from 7:30 a.m. to 1 p.m. Thursdays in the parking lot at Center and West streets. Both markets are sponsored by the Prince William Extension Service. Call 335-6285 for information. Center Offers Classes

The Center for the Arts will offer a variety of classes beginning next week and meeting once a week for six to 10 weeks. Creative writing, conversational French and musical theater are a few of the courses available. Pre-registration is required and tuition is charged for each class. The programs are held at the Center for the Arts in Manassas and Tacketts Mill in Lake Ridge. Call 368-FINE for information.