wireless network

Excuse my naivety as this is my first venture away from Windows.
I have two PC’s running Windows and a Media Player with attached HD (MKV’s)
I have installed Netrunner on my Netbook as a taster for when one of my PC’s XP has no updates from April.
The installation has been faultless and using a few guides to speed up Firefox boot amongst other things it is working great.
I can see the rest of the network when I am hard wired to my router/swich but am unable when wireless.
The wireless works a treat too but it would be handy to access my Media Player files if possible wirelessly.
Do I have to set up a “create wireless network” and where is it or am I missing something elso. Please advise.
Sorry I should have introduced myself. I’m an old codger from the UK - Hi

It might be that your devices are accessible but just not listed. If you know the ip adress of the target computer/media player you can try accessing them directly.
Just in the dolphin file browser hit CTRL+L to bring up the adressbar and type in smb://.
I for example can access my smartphone (which has a samba share) with
smb:// from within the file manager.