Do you have Business Policies set up? eBay is gradually introducing it for all sellers. Check in your My eBay under the Account tab > Business Policies.
If you have Business Policies then you can create a Pick up Only Postage policy.
In the Domestic Postage box select No Postage: Local Pickup Only.
If you want to offer postage or pickup you can set up a flat rate policy and click on Offer Additional Service and select Local Pickup Only (it's right down the very bottom of the list)
You an also create a Pay on Pickup Payment policy.
If your ID is not opted in to the Business Policies yet:
On the Sell your Item form in the heading for the section Add postage details click on Add or remove Options and tick the box to Show local pick up, then Save.
If you want to offer postage or pickup:
In the box for Domestic Postage enter your Flat Rate postage details and then underneath tick the box for Local Pickup. For some odd reason you cannot use Calculated postage and also offer Pickup.
If you want to have the listing as pickup only:
In the box for Domestic Postage click on the dropdown arrow and select No Postage: Local Pick up only
In the heading for the section Select how you'll be paid click on Add or remove Options and tick the box to show Pay on pickup, then Save.
