I'm getting married there later this year & we're from the states also, but just like u, it would have been much harder to have my family fly over here, and it is much cheaper to have the wedding there also. Most of the locations you choose will have everything provided for you, if u choose to have it, so you dont really need a wedding planner.
I looked through sites like noviascolombia.com and eventosyfiestas.com
Some cool places to check out (and i actually went over there bcz i didnt trust the pictures on the websites.. u know, a picture can withstand anything) but these are some of the places i actually visited & were still pretty nice: La Verdieri (Chia)... , Hacienda Paunchica (Chia).. they put tents at paunchica (they dont have an actual room/building) & the lady is really nice & speaks perfect english bcz she lived in DC for some time, Hacienda Rincon de Teusaca (La Calera).., Hacienda Granja de los Pinos (Chia)... i cant think of the other ones, though, but check out those 2 websites, u'll find tons of stuff and if u get one of these places, they pretty much offer everything you'd need... except for like ur dress , but everything else... food, drinks, photo/video, flowers, sometimes cake, sometimes alcohol, chapel, and an old fashioned car (rather than a limo), etc.
I looked through sites like fotopintoydiaz.com
Our caterer (Bodega y Cocina) also takes care of decoration, flowers, and set up. Also, they provided us with a wedding coordinator on our wedding day. She was there from the moment they started setting up until the end of the party.
We also used eventosyfiestas.com for other vendors.
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