Nori's Saimin and Snacks   Yes, there are fancy Big Island restaurants that feature the best produce from Waimea and Hamakua. But sometimes you just want down-home food. Hilo's Nori's Saimin and Snacks, hidden in a Hilo office complex and run by vivacious Beth-An Nishijima, is on the food-pilgrimage route that winds through the Islands. Starkly lit with fluorescent tubes embedded in the office-Styrofoam ceiling, you're not here for ambience. It's the sizzling salmon, ahi tofu, kim-chee fried rice and, of course, saimin (with the curlier “Hilo-style noodles”) that call. Nab one of the semi-private wood booths flanked by bamboo poles, eat, then get your omiyage.  688 Kinoole St., Hilo. 808-935-9133. 10:30 a.m.-3 p.m. Mondays; 10:30 a.m.-3 p.m., 4 p.m.-midnight Tuesdays-Thursdays; 4 p.m.-1 a.m. Fridays-Saturdays; 10:30 a.m.-9:30 p.m. Sundays. AX, DS, MC, VS. $.