Dub-wise, probably David Matranga was cast as Tomoki because the above series isn't English-dubbed, but there IS another dubbed anime that Nakamura starred at and his role was dubbed by Matranga... CLANNAD (both of them doing Tomoya Okazaki)
Since Tomoki isn't a particularly similar character to Tomoya aside from being a surly young man, this is unlikely. People in the dub industry make it clear that except in special cases (for example, Haruhi and Konata) they almost never deliberately cast english VA's to match seiyuus just for the sake of it; Everyone is simply cast as characters whom their director felt gave the best audition or would be most fitting. However, if a dub actor happens to voice the same character as a certain seiyuu more than once, it usually means that they can be considered counterparts. Many voice actors have happened to end up voicing characters with a certain seiyuu multiple times without it being a casting gag.
/v/'s nickname for Tomoko is "Spaghetti-tan", because of their meme about spaghetti leaking out of their pockets during socially awkward situations, seemingly for no other reason than to make the situation even more awkward and embarrassing for them. Turns into an Ascended Meme when, as a thank-you to foreign audiences, Tanigawa drew a picture of Tomoko actually eating spaghetti.
World Three, the primary scanlation group for the series, affectionately gave the manga the project title "loser girl."
"Slut-chan" for Yuu, because in Tomoko's eyes girls more socially adept than she is are "bitches" or "sluts".
What Could Have Been: According to the Japanese Wikipedia at least, the authors originally planned Tomoko not to have a single friend. The editor found this premise too depressing and asked the authors to introduce a friend for Tomoko, which is why Yuu was created.
Write Who You Know: The series is based on the authors' own experiences. The reason why Tomoko doesn't deal with bullying is because one of the authors was bullied, and that would hit too close to home.