Banggood.com is also an option, but I prefer aliexpress.com because it usually has more options and better prices.
There may be items on amazon.com that ship to Uruguay, but I haven't found any. There are some shippers in USA that will organize your purchases into one package and ship them to Uruguay, but I don't find that especially interesting, considering I have family in USA.
Uruguay aduana can't keep up with all mail, so some items, probably smaller ones, make it through without your being asked to pay import taxes. For this reason, redditors in 2020 recommend not declaring your shipments. In another 2020 reddit thread, runic3270, BardoKeeper, and others agree that small items that don't weigh too much are not stopped by Aduana.
Because they want to make the matter as confusing as possible, Uruguay mail does not use the existing tracking number, and makes up its own. This leads to a complete lack of effective tracking once the package arrives in Uruguay. The last item you see in tracking may be “handing over to airline” or “departing country of origin”. The last item may also say “arrived at destination country”.
I called Uruguay Correo/Aduana (0800-2108) and they claim exterior tracking has no way of knowing when a package arrives in Uruguay, (despite the package arriving in Uruguay by plane, at least according to tracking info). He also said that Correo/Aduana may take one month, two months, even three months to process a package sent by “simple mail”, where simple mail doesn't have a pre-approved Uruguay tracking number. Simple mail takes long because it has lower priority than those with approved Uruguay tracking numbers, where you have paid at least a small Uruguay shipment fee.
You can set up an account, and pay import taxes on shipments that aduana has intercepted at the following address:
However, the only way you will know that they have intercepted your shipment is by a notice in your mailbox. If that notice would get lost, I think you would be SOL (shit out of luck).
That system has a bad reputation of not having correct information, according to yet another reddit thread in 2020.
Not sure what this address is for: https://www.correo.com.uy/acceder