Linking words
 

I have difficulties linking the end of one word to the beginning of the next when the two vowels are different. Can you give me examples on how to fix this?
For example, for this sentence: Dónde esta el baño? I would pronounce it as Dóndesta el baño?. However, I've heard native speakers blend the final "a" in "esta" with the "e" in "el" by losing the e. Is it true or am I hearing it wrong?
One more example is "?Tiene una habitación?" How would you native speakers pronounce that sentence?

When blending one word to the next, where the vowels are not the same, the stressed vowel takes precedence. Sometimes the unstressed vowel is barely audible. Sometimes it is elided. You should have also noted by now that very few of the Spanish consonants sound exactly like their English counterparts.

So, in ¿Dónde está el baño?, this is what I hear more often than not: dóndestálbaño
You may choose to make the e in el barely audible, but most omit it.
By the way, an English speaker will often mispronounce the final l in el. This is because we have a different pronunciation for a final 'l' in English. Say 'bell' and take note of where your tongue ends up. Next, say 'all'. Same tongue position. Now say 'little'. Your tongue will actually touch two different places on your hard palate. The Spanish l is always pronounced like the initial 'l' in 'little', never like the second 'l'. So, when you're asking ¿Dónde está el baño?, make sure the l is pronounced correctly (if you just said the English name for the consonant, you mispronounced the word for 'the' in Spanish). ;)

This is how I've heard your other sentence spoken:
tienunabitación

I'm slightly confused here. I find that my tongue is in the same place for 'bell', 'all' and the first 'l' of 'little'. Is this what you mean?

That's where my Spanish 'el' is as well. :thumbsup:

Sorry to confuse.

I'm speaking primarily from an AmE point of view, in case it matters. In AmE, the final 'l' is not pronounced the same way as an initial 'l', but most people that talk about it on the internet just say that we add a syllable (the schwa sound) before saying the final 'l'. The extra syllable is much more pronounced if the vowel that precedes the final 'l' is a long vowel. Here's a video that illustrates this.

However, what I'm not hearing anyone say is that the tongue is actually in a different spot for the initial 'l' (and one that falls between vowels) and the final 'l', like in the word 'little'.
I can force the same pronunciation for both l's, but that isn't how I normally speak.

A glance at the English IPA chart versus the Spanish IPA chart indicates that Spanish only has one pronunciation of the 'l', while English has more than one. Footnote number 9, in the English chart, provides this tidbit about the final 'l':

Then how would you say:
Dirigía a un hotel ?

dirigíaunhotel

The a that precedes the u is said, but doesn't receive any stress.

Ah, cláro. Gracias por todos.
Y como pronunciar esta "Si voy a la fiesta esta noche?"

As Rusty already said, the stressed vowel gets preference: you will typicially hear either "fiéstaésta" (the "a" is audible) or "fiéstésta" (the "a" is elided).