You must still remain 1000 ft above etc. EVEN IF you are intending to land,
If you're in G airspace, and landing at an airport WITHOUT a published IAP then you can descend down to below 1000' so long as you comply with the other relevant rules of the air (rule 5 for example). There is no reason why you cannot create your own GPS or other procedure outside controlled airspace, and its not illegal UNLESS a published IAP already exists. May sound a stupid thing to do, but imagine you're coming into an airport on the coast. If you are 100% certain of your position (GPS / cross radials confirm etc) and you're over the sea, then realistically it can be a relatively safe thing to do.
Cheers
EA
