Google Books has scanned in some mid-19th century editions of Old Norse
books and made them fully available. Some of those are texts that are
otherwise hard to find. Here are some books I've found:

An Old Norse reader:
http://books.google.com/books?vid=OCLC03798616&id=BkGwSznphEIC&printsec=titlepage

Another Old Norse reader:
http://books.google.com/books?id=PdnAEidRlqIC&pg=PR1

The King's Mirror:
http://books.google.com/books?id=LgtIfLwQgX4C&vid=OCLC05178869&jtp=1

The Separate Saga of St Óláfr:
http://books.google.com/books?id=dYSBxK0Bq_gC&vid=OCLC02871528&jtp=1

The Legendary Saga of St Óláfr:
http://books.google.com/books?vid=OCLC05163436&id=u-F9Ami8McYC&pg=PA1&lpg=PA1

Fragments of the Oldest Saga of St Óláfr:
http://books.google.com/books?id=u-F9Ami8McYC&vid=OCLC05163436&jtp=90

Strengleikar:
http://books.google.com/books?vid=0Bj0efKJLGZwL8_C&id=gvAAUC1bbesC&pg=PA1&lpg=PA1

Have fun browsing those and let me know if you find any more! :)

Regards,
Haukur