I use multiple sites to share and find data.
http://dna.ancestry.com for Autosomal DNA
http://www.gedmatch.com for Autosomal DNA
http://www.familytreedna.com for Autosomal, mtDNA and Y-DNA
http://www.yfull.com for Y-DNA interpretation
https://www.23andme.com/ also does Autosomal testing
https://www.fullgenomes.com/ for Y-DNA and full genome sequencing
Then there are sites that are useful as tools, as well as some softwares that help with putting all this data into something that might make sense.
(This is a ‘work in progress’ post, and will be updated later)