Sightreading Genie by PracticeSpot.com is a great tool for beginning sight readers. This tool allows you to choose from 4 difficulty levels and proves you will a large amount of short musical examples to play. It is designed for piano but many instruments can use it because it uses treble and bass clef.
This is one of the resources I will discussing in my new book 30 Days to Reading Music with Ease which is due out Monday, May 28th, 2012. This book will include many more tips, tricks and resources to teach you to read music fluently and eliminate the confusion of musical notation.
Until next time ... Practice Less, Play Better