I think the best place to start is with the Eddas, which are our best primary sources on Norse mythology. The poetic Edda is a collection of old Norse poems, and the prose Edda was kind of a mythological encyclopedia and poet's handbook for people who wanted to understand the old poems and maybe write some of their own. Keep in mind that these were written down in Iceland long after the Viking Age, so they represent only a fragment of what was probably a much more diverse set of mythologies, and it's hard to know just how accurately they portray what people thought and believed centuries before. The poems were also all written for different purposes and some of them are probably missing key parts, so reading the Eddas should actually leave you with a lot of new questions. As a scholar, I think that's one of the coolest things about Norse mythology—each time I read it, I see it from a slightly different perspective, raising new questions and suggesting new meanings.

The Eddas can be found in a lot of different editions and even for free online. There's no 'right' or 'wrong' edition, as long as you find it enjoyable to read. My personal favorite is Patrica Terry's Poems of the Elder Edda. I think the Penguin editions tend to be very good, and they also come with excellent introductions. They've currently got a handsome set bound in art inspired by JRR Tolkien, which I think is pretty neat. You might also be interested in The Saga of the Volsungs, which is a mythological cycle (i.e. heroes rather than gods) that has clear ties to the Lord of the Rings but more importantly for your interests it gives another perspective on many of the poems in the Elder/Poetic Edda.

For more recent scholarly studies, the best place to start is Brink and Price's The Viking World, which has about sixty pages on pre-Christian religion and belief. You should also check out Neil Price's The Viking Way. Price does a brilliant job bridging mythology, archaeology, and ethnographic comparisons with modern northern religions (i.e. shamanism). It's very well presented and a pretty compelling argument overall, but it's worth remembering that this is a hypothesis about how Norse religion worked and not a definitive exposition. He introduces some of these ideas in a very good set of lectures which are available free online. Another option is Anders Andrén et al's Old Norse Religion in Long-term Perspectives (2006). This is a collection of short articles. It's not comprehensive (unlike the other two books above), and some articles are more accessible than others, but there's bound to be something that interests you, if you can get your hands on it.

These academic books might all be a bit more expensive, however, so it's best to ask at your local or university library to see if they can get a copy for you. Most libraries should be able to get them in about a week or two, although if it's through Interlibrary Loan, there's usually restrictions on how long you can keep them checked out. But librarians love helping with this kind of thing, and they might even be able to come up with suggestions of their own—it's what keeps them in business!

Hiya, to clarify, you're asking for educational / academic recommendations?