You can find neighbors by asking in the #nodesharing channel on the official IOTA Slack.
If you are not already a member, you can sign up here: http://slack.iota.org/
Within the GUI, select ‘Tools -> Edit Neighbours’ to add neighbours.
In the text box below ‘Neighboring Nodes’ you need to add a different node to each line. Be careful not to add an incorrect character or any extra space.
It is recommended that you have between 7 and 9 neighbours. All must add your node in return as, if they do not add you, you will not be able to connect to them. Having more than 9 neighbours is highly advised against, as it is harming the network.
Click ‘Save’ and the GUI wallet will restart.
It is important to note that having a static IP is required to use IOTA for any length of time. If you have a dynamic IP it will change roughly every 8 hours, meaning you will need to periodically ask all of your neighbors to update your IP; this is obviously not sustainable.
You can use a service such as noip.com to get a static IP - see our guide here for instructions: http://iotasupport.com/staticip.shtml
To see if you are connected correctly to your neighbours, select ‘Tools -> View Neighbours’
For each node that you have added you will now see ‘numberOfAllTransactions’, ‘numberOfNewTransactions’ and ‘numberOfInvalidTransactions’.
If all of these are shown as 0, then you are not connected to that node. Perhaps they are offline or they have not added your IP address.
If you are properly connected you should expect to see something like this:
It is desirable for your neighbours to have a high number of NewTransactions - this means they are seeing fresh transactions that you have not yet received.
It may be the case that only a few neighbours are sending you transaction information at any given time.