Hola Edwyn and hola amigo Dan!!!
Sorry for my late response, I've been having a lot of work this week (and also last week) but it is a pleasure for me to answer, participate or comment on this forums, since it makes me happy to help other interested in my native language,\as I have said before in other posts, it is an honor and makes me feel proud that people from other countries take an interest in Español or Castellano as it is called in some latinamerican countries). Also excuse my english, as it not perfect, but I also do enjoy practicing it here, whilst , helping out with your questions!.
Anyway...primero lo primero (first thing first!)...Yes! I used the famous "lo" , and I know "lo" and "le" sometimes seem a little bit hard to understand, and to be honest, and while reading your comments, I did a question to myself, (in spanish of course haha) How does it work? How/when/or why do we use "lo" and "le"?. And the mexican hamster living in my brain just responded "No tengo idea!" haha, so , not being a spanish teacher or spanish linguist myself (I am just a native speaker and have found the intereset to try to learn more and more), I had to think this a lot and also search for some more information. So , 'lo' is a direct objetc and "le" indirect Object. The easiest explanation I found was here.
http://www.studyspanish.com/lessons/iodopro.htm and also here
This last page says at the end
Loísmo: In some regions, you may occasionally hear the use of lo as an indirect object instead of le. However, this practice, known as loísmo, is considered substandard and should be avoided by those learning the language.
In other words, It might be used a lot in Mexico, but it is not a rule. Spanish has a million ways of saying things, so, why not just change the sentence a little bit, and you can say the same things, with different words.
Also I found this example that i think is very easyly understood
le is a pronoun that means "to him/her" or "for him/her." In other words, it's an indirect object pronoun. (In some cases it will mean "to/for you" where "you" is "Usted.") So if you want to say something like "I'm giving him the book," you have to keep in mind that "he" is not being given. The book is being given. The book is being given "to him" so you would say "Le doy el libro."
If you wanted to replace "the book" with a pronoun, you'd use "lo". If it were a house, you'd use "la". Those are the direct object pronouns for the singular. Direct objects are receiving the action -- so you can ask yourself, "What is being given?" if the verb is "give", "What is being read?" if the verb is "read", etc.
If you want to use both le and lo together, "I'm giving it (el libro) to him," le becomes se to make pronunciation easier, and the sentence becomes "Se lo doy."
I hope this info helps clear that first question and the usage of indirect objects.
Now , for the 2nd subject, which is vernacular phrases, slang language, accents and idioms.
This is one of my favorite subjects related to my language, Spanish! and I also find it very interesting in other languages, like english, french and german.
When I hear someone from Caracas, Venezuela speak, my jaw drops instantly! It's so beautiful (at least for my ears)!. Same thing with the "Rolo"(Bogotá) accent from Colombia or even some northern accents from Mexico. It would be my all time dream to be able to identify all the accents and where they belong to , at least from spanish speaking countries, and this is still very hard for me, now imagine how I feel trying to identify this in German.
In the case of english, I have also studied , or tried to, a lot!. But as you mention , is not just the accent, but also the word usage and some words that make a difference to identify where the speaker is from.
If you wish to know a little bit more, at least from Mexican slang (and the different varities) , you can make me a list of things, frases or words in english that you want to know how to say in slang mexican spanish and i can write it down. It is going to be fun! haha
I will include a small (fake) conversation between two guys , from my city, and if you don't understand, don't worry, I will put a more standard spanish version.
-Que onda wey?
-Nada, aquí "nomas", jalando.
-Vas a caerle al party en la noche?
-Simón, ahi nos vemos wey.
-Arre wey, "alra"
Spanish book version haha
-Hola, que hay de nuevo, amigo?--(-Wey or Buey is a very VERY popular way of saying dude, bro, friend in Mexico. Onda literally means wave, but in this case is like " What's up bro?")
-Nada, estoy aqui nada mas trabajando- (nomas short for "nada mas" which can be use like the english, only or just. Jalar means "to pull" but we use it here as a slang version for Working.)
-Vas a ir a la fiesta ésta noche?- We use the english word Party sometimes, and "caerle" means something like "to fall" or "drop" just like the english "Drop by".
-Si, ahí nos vemos- Yes, I'll see you there. Simón is a name, Simon, in english, but since it starts with "SI" sometimes we use it as "yes". Wey is seen again in this sentence.
-O.K amigo, nos vemos al rato- "Arre" is the spanish word used when you are in a horse and yell "giddy up" haha but we use it a lot to say OK, at least here in my city, "alra" is short for "al rato", or later on,
I hope you enjoy it!
Que tengan buen dia, see ya "alra"!