¿Astrid y Gaston? Ummm, no.
Good places include La Mar, Pescados Capitales, El Mercado, Kapallaq & Segundo Muelle. The last is a chain with several outlets in the Lima metropolitan area including San Isidro, Miraflores & Surco.
If you want the real deal I recommend that you grab a taxi to Av. La Mar, a still-scruffy-looking street in Miraflores. On or just off Av. La Mar are the first three restaurants listed above. Of the three, my facvorite is El Mercado. Warning: get there early, especially on weekends. It's a popular place.
I also recommend Los Cavenecia, in Barranco. Not exactly a cebichería, but they serve good seafood for both lunch and dinner.