Italian cooks, like those elsewhere, are quite willing to buy pre-prepared foods, especially when the preparation entails a fair amount of work, and leaves one with a body part that must be used some other way. This is certainly the case with squid for frying: while the rings the body is cut into will fry evenly, the tapering tentacles will not -- by the time the thicker bases are done the tips will be overcooked or even burnt.
One solution for the home cook who buys whole squid is to use the tentacles to make an inzimino (squid cooked with spicy greens), but many simply buy the rings ready-to-cook, batter them when they get home, fry them until golden, and serve them with lemon wedges.
The common companions for totani rings are small fry, and gamberetti, or shrimp. Figure a pound of each (500 g) to serve 4-6 people, and fry the fish in small batches lest the oil cool and get absorbed by the food.
Much more detailed instructions for preparing a fish fritto misto, with a recipe for batter as well.
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