Both serious and casual collectors haunt house sales, flea markets, auctions and antique shops seeking treasures of the past - from glassware to gargoyles, furniture to folk art. But hitting the road, as so many of us are doing this summer, broadens the browsing territory. Many aficionados refer to the definitive Kovels' Antiques & Collectibles Price List (Three Rivers Publishing paperback, $14.95). Here are co-author Terry Kovel's tips for top shows and antiquing spots.

Renningers markets are the big draw. In Adamstown, it's the Antique & Collectors Market every Sunday, and in nearby Kutztown, the Antique & Flea Market, open every Saturday. Three times a year the Renningers Extravaganzas feature more than 1,200 dealers from 42 states, one of the USA's largest shows (upcoming dates: June 25-27, Sept. 24-26). ''When the big events are on, you can't get a room for miles Ñ there isn't a flophouse to be had.'' Clotheshorse alert: Outlet mecca Reading, Pa., is between the two towns.

Lebanon, Ohio

This former Shaker settlement between Dayton and Cincinnati boasts beautiful old homes and a village green surrounded by 19th century storefronts. The Shaker furniture is gone, but ''they have tons of specialty shops that feature Shaker items.'' And there's a Lebanon antiques show in January.

The thrice-yearly Brimfield Antiques & Collectible Show - the town is in the western part of the state, between Springfield and Worcester - fills 23 adjacent fields (upcoming dates: July 7-12, Sept. 8-13). ''You can find anything from 18th century furniture to Pez containers. And you always find strange things. I collect textiles, and I bought an 1875 handkerchief for $10 last time.'' Fanatic foragers ''argue over who's bigger, Brimfield or Renningers.''

Occupying seven buildings plus outdoor tents at the town's Fairgrounds, the 30-year-old Ann Arbor Antiques Market is held every third Sunday April through October and the second Sunday of November, plus the preceding Saturday in April and September. It offers an unusual policy of guaranteeing every item as represented. An hour's drive away is Marshall, ''which is one big antique town.''

''Twice a year they turn the whole town into an antiques show'' that's renowned for Americana and country-chic items (upcoming dates: Oct. 2-4). From museum-quality folk art to Tiffany silver, the goods fill two 19th century dance halls and two tent pavilions just outside tiny Round Top - about a 90-minute drive from Houston, where Carolyn Thompson's Antique Center of Texas has ''very good prices - and there must be 60 shops in the area.''

''For 18th century Americana you go to the East Coast,'' but here the finds are oak furniture and ''Western-oriented cowboy stuff.'' A half-hour's drive from Phoenix, Glendale has more than 90 antique shops, including The Apple Tree, a multidealer shop specializing in early country and primitive pieces. Few towns in the West have ''as many shops in close proximity.''

Santa Monica shops - most on Lincoln Boulevard or Montana Avenue - have ''a bunch of California pottery and '50s furniture.'' And there's an antiques show the second Sunday of each month at the Rose Bowl in Pasadena. ''It used to be you went into L.A., to Melrose, and it's still fun because there are kooky people and shops, but a lot have moved.''

The Scott Antique Market, which describes itself as ''Brimfield of the South,'' fills 2,500 booths in two adjacent Exposition Centers, each the size of six football fields. Held the second weekend of every month, it includes an outdoor area with ''an enormous amount of garden stuff: implements and statues and what-not.'' Buses transport shoppers between areas. Scott has a sister market half this one's size in Columbus, Ohio (the fourth Friday-Saturday, November-June), ''but that one's not as scenic.''

The twice-yearly Atlantique City show packs the Convention Center with thousands of dealers, who ''book rooms a year ahead'' (upcoming dates: Oct. 17-18). Its 1,600-plus booths feature antiques and collectibles from fine arts to ''slot machines, country-store things, grown-up wind-up toys . . . . They also have things like art pottery from Paris.'' The show's computer system points treasure-hunters to specific dealers in 1,174 categories of goods, and its researchers track trends (hot now: Roseville art pottery, Limoges porcelain, Fiesta dinnerware, Jensen silver, Moderne furniture).

Every January - high season in South Florida - ''they promote (building) tours and events and antique shows all together'' in the art deco district. ''I went down for one of the four weekends, and there were 2,000 dealers in town for two shows. . . . They get a lot of foreign trade at these shows - French, German, English, Japanese - so you get easily transportable finds.'' Lincoln Road, near the Art Deco hotels, has a flea market Sundays, plus shops including the 28-year-old Circle Art and Antiques.