If you’re using samba to share your files in network,there’s a recommended GUI tool system-config-samba that you can easily create,delete and configure shares with a graphical interface.
First,make sure you have installed samba server in your ubuntu.
And now,you can install system-config-samba from System->Administration->Synaptic Package Manager.Search “system-config-samba” in search box,choose to mark and click Apply to install.
After installed this tool,you can launch it from System->Administration->Samba.

To create new share,click on Add Share,and in this screen type details.


To get access to the share folder from Windows PCs in the network,go to Start->Run and type \\hostname\share_name.(or \\IP address\share_name),you can use this command in terminal to get your ubuntu hostname:


Or,just type \\hostname after Start->Run and you will get all shares from this PC.
if you want to share files between Ubuntu PCs,using sshfs maybe more easily and friendly,just like mount windows drives on your desktop.
Networking ubuntu PCs with sshfs