I'd suggest a steady diet of Perfect Duluth Day.  It will cover all of what you mentioned above.

-Take a bus to West Duluth, have lunch at Beaner's Central, visit Central Sales, and then walk around the neighborhood. 

-Get a map of the Superior Hiking Trail, and walk the length of it inside Duluth's city limits over the course of a few weeks. There are lots of other trails that are fun to walk, too. 

-PDD archives ... oh yes. 

If you're at the UMD library, and you're looking for something to do--the history center upstairs is pretty interesting. Also, if you're there late at night, an evening spinning through the very old Duluth newspaper microfilms are pretty interesting/hilarious. Also, there are lots of books on Duluth history in the stacks.

Yes, PDD archives are made just for you.

When I was a student at UMD, I found the Celtic Jam at Sir Ben's on Thursday nights and consequently the Tamarack Dance Association.  I've come to accept that not everyone loves this stuff as much as me, but my early connection with musicians in Duluth was a great way to get off campus and is likely why I ended up sticking around. There's also the monthly square dance.

Start by Googling "Duluth Ripsaw History." The first 10 links will offer a shorthand lesson on the subjects you mentioned.

I love Duluth. I'm originally from Plainfield, WI. I moved up to Superior to go to college in 2006. Fell in love with Duluth and Superior, coming from a town full of fields. I moved away (hour in a half south) couple years ago. Even though it's driving distance, I miss out on everything and miss the city like you wouldn't believe. This site is the only thing that really keeps me updated to what is going on. Thank you!

Welcome to Duluth and your quest for information.

Volunteer at different arts and service organizations and at diverse events and talk to the other volunteers. Also, ride the bus.

Go to art openings and literary events and talk to people, you will be amazed at the talented people who call this city home.

And don't forget the Zinema--a great art film cinema with Two Hearted Ale

+1 for the SHT...though it's getting a little late in the season to do any major hiking. November brings hunting season, and a lot of the trail cuts through prime hunting land. They usually post restrictions on the Superior Hiking Trail website.

Off topic but, Stephanie -- Plainfield in Waushara County?  I grew up in Almond!  Small world.  I always feel so out of sorts when I go back to visit my family -- all those monocropped fields of corn or soybeans, it's depressing -- and I'm so, so, so glad to get back to Duluth.