I was in Sicily for the first time in April and we stayed in this place in Bonagia http://www.hoteltonnaradibonagiasicily.com/ just bout 10 mins drive from trapani on the west coast. But if I was going back i'd probably stay out near San Vito Lo Capo. It's less than 2 hours drive from Palermo. It's a lively little town with an amazing beach. It's also close to the Zingharo reserve which has amazing beaches too. http://www.parks.it/riserva.zingaro/Eindex.php
I'd also recommend visiting the greek ruins in Segesta http://www.bestofsicily.com/segesta.htm and stopping for lunch in the town of Castellamare del golfo http://www.tripadvisor.com/Restaurant_Review-g608929-d1145791-Reviews-Ristorante_La_Cambusa-Castellammare_del_Golfo_Sicily.html
I haven't been over the other side of the island only to fly home but I've a friend whos been a few times and he always stays near san vito lo capo.
http://www.hostelworld.com/findabed.php/ChosenCity.San-Vito-Lo-Capo/ChosenCountry.Italy heres a site with some great guesthouses and apts. Better value really than hotels.
Enjoy!! almost 10 years ago