Apple nearly saw a repeat of last year’s sellouts on the weekend with widespread, but brief, iPhone 3GS shortages at many of its US retail stores.

Keeping to its now traditional approach of tracking iPhone supplies closely in the immediate wake of a launch, Apple has posted an iPhone 3GS availability tool that lists stock by store and by model — and which has hinted at continued strong demand for the third-generation handset a week after it first appeared.

The weekend began with only minor shortages that saw 29 of 257 shops nationwide reporting any kind of limited availability. By Sunday evening, however, very few stores had any stocks of the white iPhone 3GS model while only the white 32GB model was available at more than 52 percent of stores. Black versions of 16GB and 32GB models were only available at just over a third of stores at 35 percent each, and about 39 stores had no stock whatsoever.

A day later, the situation had improved substantially, with only six stores reporting no iPhones in stock and only a small amount more going without one or more models.

Whether or not the situation will remain the same in weeks to come is hard to tell. Last year’s iPhone 3G launch saw even more severe shortages around this time last year and maintained a similar dire state for weeks afterwards, but it’s possible both that Apple has better prepared itself for its latest launch as well as that economic woes have kept certain customers out of stores.