Q: Where can I find background information on paintings by Louis Ritman? I'm especially interested in his early paintings of fashionable ladies dating from the first quarter of the 20th century.
A: "Louis Ritman -- From Chicago to Giverny: How Louis Ritman Was Influenced by Lawton Parker and Other Midwestern Impressionists," by Richard H. Love, is available for $65 plus $4 shipping. Order from Haas-Mumm Publishing Co. Inc., 100 E. Ohio St., Chicago, Ill. 60611; (312) 664-9620.
Q: I collect antique jewelry shaped like reptiles, including iguanas, alligators, dragons and serpents. Where can I find others?
A: Reptile jewelry has long been a favorite with collectors; some believe such pieces bring good luck. Antique pieces shaped like various animals, birds and insects are in the 979-page "Official Identification and Price Guide to Antique Jewelry," by Arthur Guy Kaplan, available for $21.95 postpaid from House of Collectibles, 201 E. 50th St., New York, N.Y. 10022; call (800) 733-3000 to order.
Magnificent reptile pieces produced by Cartier include a diamond-studded snake necklace and a gold alligator neckpiece encrusted with diamonds, emeralds and eyes of rubies made for Maria Felix, a Mexican film actress. Another piece is a breathtaking diamond- and ruby-studded gold bracelet shaped like a chimera (or fire-breathing monster) with crossed heads, pictured in color in "Cartier -- The Legend," by Gilberte Gautier, available for $25 postpaid from Cartier, 653 Fifth Ave., New York, N.Y. 10022.
Q: Where can I find old radiator caps? I'm especially interested in figural ones.
A: Write to Old Car and Gas Station Memorabilia Wanted and for Sale, Box 173, Deerfield, Ill. 60015. If you want to sell an item, enclose a description of it and an addressed, stamped envelope for a reply. You'll also find sources in the bimonthly Check the Oil magazine, available for $16 a year, or $3.50 for a sample issue, from the International Petroliana Collector's Association, Box 1000, Westerville, Ohio 43081.
Q: I recently started collecting glass toothpick holders. How can I learn more about them and their values?
A: You can find out everything you ever wanted to know about toothpick holders by joining the National Toothpick Holders Collectors Society. It offers an individual annual membership and monthly Toothpick Bulletin for $10 (or $15 for two collectors). Write to Joyce Ender, treasurer, Red Arrow Highway, Box 246, Sawyer, Mich. 49125. Two books on toothpick holders are available: "1,000 Toothpick Holders with Price Guide" and "Rare and Unlisted Toothpick Holders with Price Guide." Both are $15.45 postpaid from Antique Publications, Box 553, Marietta, Ohio 45750; (800) 533-3433.
Anita Gold can be reached by writing Anita Gold, Maryland Living, The Sun, Baltimore 21278. Selected questions will appear in her column. The volume of mail makes individual replies impossible. When writing sources listed in this column, enclose an addressed, stamped envelope for replies.