Run by John Maternoski, Portland Design Events is "The premier website for finding and sharing architecture and design-related events in Portland, Oregon". If there's an important design lecture, party, or in Portland, you'll find information about it at www.portlanddesign.org.
Next Portland "writes about multi-family residential, retail, cultural buildings, educational buildings, hotels and other large projects happening in the City of Portland. We cover both new buildings and major alterations or additions to old buildings. Our blog posts are exclusively written about projects that are either still in the design phase, or are under construction." From www.nextportland.com. Next Portland has a great map feature that shows where these buildings will land.
There are so many questions to ask when you're building an ADU. This website is a great place to start. Accessory Dwellings is "A one-stop source about accessory dwelling units, multigenerational homes, laneway houses, ADUs, granny flats, in-law units…" From www.accessorydwellings.org.
PortlandMaps is a great public resource that has information about taxes, lot sizes, owners of property, and more. Search for an address and find the year a building was built, the zoning of the property, transit lines, permit information, and a lot more. If you're going to buy a property, this is definitely a good place to check first.
A blog about design in Portland by Brian Libby. There aren't many great architecture critics/writers in Portland, but Brian Libby is definitely one of them.