I honestly don’t recall how I came upon this site yesterday evening, but I did: Old English at UVA. The site links to an online version of this book, Introduction to Old English, by Peter S. Baker. Here’s a description of the book:
Introduction to Old English is a new textbook published by Blackwell Publishers. The book is aimed at students whose interests are primarily literary or historical rather than linguistic; it assumes no expertise in traditional grammar or other languages, but it provides everything the student needs to read Old English well. The book includes an anthology of prose and poetry. The entire grammar is available on-line, and the anthology is also available as part of the Old English Aerobics web application.
You can find the online version of the book here.
The Old English Aerobics Anthology can be found here. All of the words in each piece are clickable, and clicking on them brings up a glossary entry for the word. On many of the selections of literature, you can also choose to select idioms or clauses. And, on a few of the selections, you can select audio, and hear the Old English spoken aloud.
Other useful pages: