Can anyone recommend some guided anapanasati resources on the Web?
The best is to go to directly to the Sutta or what the Buddha directly had to say about it. There are 2 good translations by Piya Tan:


Anapanasati Sutta
Anapanasati Sutta, Trilinear edition


A more detail explanation of the Sutta is available in Mindfulness with Breathing: a Manual for Serious Beginners, 2nd edition which does a wonderful detailed explanations. (Don't use the 1st as this is a poor translation.) In addition there are some lectures by Budddhadasa Bikkhu: Anapanasati by Ven. Buddhadasa.

For the very basics have a look at: Mini Aanapana.

Also 


Anapana Sati Sutta by Bhante Vimalasiri
Anapana Sati Sutta by Ven. Bikku Bodhi


would be helpful guides.

Also you can try to locate a more formal retreat like through: http://www.dhamma.org/en/index or http://www.buddhanet.info/wbd/ which will solve the issue that you do not have a teacher.