could somebody help me choose the idiomatic prepositions?

Homer Simpson is a character [from/in/on/(others)] a popular TV series.
Question: Is someone or something in or on a (TV) series?

Homer Simpson was featured [in/on/(others)] several ABC commercials in 2005.
I was told to use "in" with "commercials", but I noticed native speakers don't always follow that rule of thumb. Does adding "ABC" in front of "commercial" change anything?

Homer Simpson is not allowed to log in [to/on/(others)] EnglishForward.com.

I hate prepositions. Thanks Emotion: smile
Generally speaking, these will work. That doesn't mean that no one ever uses others. Alternations between in and on are not that unusual.

in a commercial
in a series
on a program

Adding adjectives doesn't change anything, as far as I've observed.

log on to www......com

I hate prepositions.
That's so sad, because they speak so highly of you. Emotion: smile

I'd respect the frequency indicated by the hits.

These may be helpful connotations.

3,580 for "featured on commercials" I'd read this as: on their face/surface
14,100 for "featured in commercials" I'd read this as: in their content

6 for "character on a popular series" presented on the stage, like in theatre
2,290 for "character from a popular series" I know him from there
7,550 for "character in a popular series" involved in the action of the series
Students: Are you brave enough to let our tutors analyse your pronunciation?
I hate prepositions.
That's so sad, because they speak so highly of you. Emotion: smile

LOL, what do you mean? Prepositions speak highly of me? Emotion: rolleyes Well, they sometimes/often give me trouble, but not very often, I have to say. So I don't really hate prepositions, after all. At least not as much as I hate the present perfect continuous! I guess that's my worst nightmare... Emotion: wink

@Marius: yeah, maybe sometimes the general context could influence the choice. Anyway, Google results give you no context (unless you check 'em all), and by the way we all know that Google can't count at all, so those numbers don't tell us anything.

Anyway, thanks a lot. Emotion: smile
LOL, what do you mean? Prepositions speak highly of me?
It's a take-off on a common exchange used to gently make fun of someone who uses the exaggerated formula "I hate ...". (Of course the typical usage has a person or group of people in the position of the direct object of hate, not inanimates like prepositions.)

-- I hate people who don't park between the lines.
-- And they speak so highly of you!

Wow. I didn't know that, thanks.
And I would never have figured it out. Because... if someone speaks highly of me, what prevents me from criticizing them anyway? Hehehe Emotion: wink
So it doesn't make much sense to me, but it's not a problem. If it's kind of idiomatic, it doesn't have to make sense.
Students: We have free audio pronunciation exercises.
The idea is that you should feel ashamed for saying that you hate someone who loves you!

Hmm, on second thought, maybe it actually make some sense...
Well, I'm starting to get confused, I don't know who or what I should hate anymore. Next time someone speaks highly of me, I'll have to think about it.

PS: Wait... I got it! I know why I can hate people who speak highly of me... Because they shouldn't have spoken highly of me in the first place! Because they should not talk about me at all. They should all mind their own business! Emotion: wink