Best source: http://www.portlandhikers.org/ Excellent forum where you can find out current conditions, and a Field Guide that lists local hikes--subject to the caveat below about this year's snow levels. Retired Jerry, who writes articles for BPL, has done a lot of the writeups for the Portland Hikers Field Guide!
Maps: There are new Green Trails maps of the Gorge this year; I haven't seen them yet. The US Forest Service map, "Trails of the Columbia Gorge" is good for planning.
Snow levels are low, low, low for this time of year. Here are pass cams as of this morning:
The extended Gorge loops go well over 3,000 feet (most to 4,000) and unless it warms up really soon (not likely given the current extended forecast), you are going to be in deep snow on the higher sections of all of them. If it does warm up, stream fords on loops like Eagle-Tanner or on upper Oneonta Creek will be downright dangerous. Everything (flowers, snow conditions, backyard gardens, you name it) is almost a month behind normal right now.
You can do out-and-back overnight trips on Eagle Creek and Herman Creek. Certainly Eagle Creek to 7 1/2 Mile Camp and back is well worth doing, and the waterfalls (around every corner) are magnificent. You won't get much above 7 1/2 Mile Camp, and you certainly won't get to Wahtum Lake, which is 4,000 feet and in a north-facing basin with heavy old-growth forest.
Another possibility is the Opal Creek hike down near Salem, probably the most spectacular old-growth forest you'll ever see.
You'll have to check on conditions; as of last week the trail above Jawbone Flats was still snowy. The bridge is marked closed (one of the two handrails disappeared a couple of years ago and the log is at a slight slant), but should be just fine if it isn't too wet. If either snow or bridge is a problem, you could hike a mile up Battleaxe Creek from Jawbone Flats instead and hopefully find a place to camp. I'm hoping to do this one next month, too.
Be prepared for rain!
The funny (as in funny-peculiar) thing is, that folks were hiking snow-free to well over 3,000 feet elevation back in January! This is the second year in a row in which spring (by the calendar) has been more wintery than winter!