Hi Josh,
You are not alone in being daunted by Gordon's book! It will come
in handy eventually, but in the meantime, a lot of people recommend
Anthony Faulkes' "A New Introduction to Old Norse" [
http://www.shef.ac.uk/viking-society/ ], comes in three volumes:
grammar, reader and glossary. Some other websites for beginners
which you might want to check out:
Old Norse Online (Todd B. Krause and Jonathan Slocum; 10 lessons +
grammar + runes)
http://www.utexas.edu/cola/depts/lrc/eieol/norol-TC-
X.html
Old Icelandic Course Materials (Tarrin Wills: referrence grammar +
texts: Iðunn and Skaði, Þrymskviða + vocabulary. Like Gordon, the
grammar is more for referrence, but you can click on words in the
sample texts for definitions, and it has more explanitory notes.)
http://teaching.arts.usyd.edu.au/english/2000/icel/
Henry Sweet "Icelandic Primer" (an old book, but still with a
difficult subject I find it helps to see how different people
explain it)
http://www.gutenberg.org/etext/5424
Materialien und Erläuterungen zur Grammatik des Altisländischen
(Einführung in die altisländische Sprache, Hartmut Röhn)
http://www2.rz.hu-berlin.de/bragi/b4/b4fornislenskukver_de_hr.pdf
Cours d'Islandais Ancien (French introduction to Old Icelandic, with
grammar & parallel Norse/French texts)
http://anamnese.online.fr/islensk/
Some more suggestions for learners of Old Norse (whatch out though,
some of the links on this page are broken):
http://has55.www9.50megs.com/OldIcel/LearningOldNorse.html
Llama Nom