Firstly,
Google Maps are to cartography what children's bicycles are to space exploration – i.e. a useless embarrassment.
That bit covered, if you want online maps then the
Bayern Viewer, as suggested by Freising, is the way to go for topographical maps.
For printed maps, you need the products of the
Bayerische Landesvermessungsamt. These are available in 1:25,000 (TP25 series) or 1:50,000 (TP50 series) scale, although tend to cover only a smallish area. From their homepage, click on the "Topographische Karten" link under "Freizeit".
For the Alps, the Bayerische Landesvermessungsamt also produce 1:50,000 topographical maps (UK series) that cover a larger area than their TK maps. Alternatively, some areas are also covered by the
Alpenverein maps, which are also good.
Bear in mind that Ordnance Survey remains unrivalled in terms of quality, so you will have to adjust. Avoid all maps apart from those from the Landesvermessungsamte and the Alpenverein – a few minutes spent perusing a Kompass map, for example, will soon have you either laughing or crying.
If you're not in Bavaria then you will have to check out the products of your local Landesvermessungsamt. Unlike in the UK, mapping is undertaken regionally here.

Bayerische Landesvermessungsamt 1:25,000