como se dice...

[Maria]

"No te he visto por mucho tiempo", or "Hace mucho tiempo ne te veo" - is this the right way to say to a person who you didn't see for a long time? Are there any other informal ways of saying smth like "Haven't seen you for ages"? And also "Haven't heard from you for a long time"?

[Eric]

"No te he visto por mucho tiempo" is correct, however I think it's more common to say "hace mucho tiempo que no te veo". Anyone else agree?

[Tomisimo]

The options Eric gives are right:

Hace (mucho) tiempo que no te veo
No te he visto por mucho tiempo

You can also use some more coloquial sayings:
¡Qué milagro que te dejas ver!
Cuanto tiempo sin verte
etc

[atnbueno]

Also one quite similar to "Haven't seen you for ages": Hace siglos que no te veo

And one more: ¡Dichosos los ojos!

Also Hace mucho (tiempo) que no te veo

[Maria]

Thank you so much guys!! And "dichosos los ojos" - I find it very cool and funny And what do you usually say in case the person didn't write or call for a long time?

[atnbueno]

How about "¡Estás vivo!" ("You're alive!" ) or "Conocí hace mucho tiempo a alguien clavadito a ti" ("I knew someone just like you long time ago" )

[Maria]

Originally Posted by atnbueno

How about "¡Estás vivo!" ("You're alive!" ) or "Conocí hace mucho tiempo a alguien clavadito a ti" ("I knew someone just like you long time ago" )

That'll do, thanx!