Yeah, google's physical/terrain version of the map used to be awesome. Like you said, now the topo lines disappear if you zoom in too close. It sucks.
CLS, you can get the stream data in google form as well as in GIS form. On this site:
http://www.pasda.psu.edu/uci/SearchResults.aspx?originator=Pennsylvania+Fish+and+Boat+Commission&Keyword=&searchType=originator&entry=PASDA&sessionID=8227005442015911131126
The lightning bolt takes you to google, the earth to PASDA maps. Same background info in both.
But mainly, I have 2 ways:
1. I have a Garmin sourced software package for a handheld GPS unit that also works on the computer. It's easy to use but not very accurate, as many smaller features are "smoothed" to save memory in the handheld unit. So a draw in a hillside, for instance, may show up as far less of a draw than it really is. Can have this on the computer or "in the field" on the GPS unit.
2. On my smartphone I have the PA fishing app. You can have a street map, satellite, or USGS topo map as the background. The USGS topo is very accurate but not as user friendly. Also, you gotta be careful that the phone is on Wi-Fi, as if you start scrolling around maps on mobile you rack up data usage awfully quickly, or just as often in canyons and such, don't have service at all. So this isn't an ideal "in the field" method.
Also on the smartphone I have the HUNT GPS app, which gives you landowner info. Same drawback regarding wifi/mobile data.
In the end, it's a combo of sources, using multiple services. I use the PASDA/google combo to scout at home, or find some wifi and the PA fishing app on the road. Then you switch to the GPS version to orient yourself with what it looks like there. Then use the GPS in the field.