I create my custom people editor in SP2010... but in Infopath 2010
forms it doesn't work.
I read that there is another control, named Contact Selector
I am not clear what is your problem and why you have it but I'll try to shoot anyway.
Contact Selector is Infopath 2007 control replaced in Infopath 2010 by Person/Group Picker control as well as there are no direct match in controls or formats of Sharepoint and Infopath forms (especially if you are on Sharepoint Foundation, which lacks IPFS - Infopath Forms Services permitting to run Infopath forms in browser.
As far as you are lacking in Sharepoint Foundation the ability to run Infopath forms in browser through IPFS, the Infopath People/Grup Picker should be configured to query Sharepoint, otherwise they will be picking local computer users and groups which are different from Sharepoint users and groups.
Well, this all depends on you configuration, installation, usage and configuration which you forgot to mention.
So far, from your question, I cannot foresee why there should be problems in using Infopath People/Group Picker in Infopath form.