Okay, so ここ would be seen in use with いる / ある then since it defines a place while これwould be used with です because it is depicting "this is an umbrella."

On a side note, I completely forgot about に. My bad. :P I knew I was forgetting something when I asked the question. I was going to type ここに傘あります。Genki said that the place where something is located with いる / ある would be at the beginning of the sentence, so would that be correct?

It just confuses me because genki will use both interchangeably.

I will see something read as 「図書館が喫茶店の前あります。」 and then later on it will say 「鉛筆は机の上です。」

Thanks for the help! :D

No. 〜こ = place, 〜れ = thing.

Google "kosoado"

That is grammatically incorrect but understandable. You need a particle after 傘 there.

What? What a turd is Genki! It can be, but it's not required.

Hi, let say if I met a old school mate out of the blue at the shopping mall. Should I say "高島屋でミューラーに会いました/お目にかかりました。" or "高島屋でミューラーにぶつかりました。"?

Only 「高島屋でミューラーに会いました。」 is close. To make it more natural, may I suggest that you use the word 「ばったり」.

「ばったり会う」 = to run into (a person)
「高島屋でばったりミューラーに会いました。」 would be perfect.
___________

Use 「お目にかかる」 and you will lose the "accidental" part of the meaning. You knew you would be meeting the person.

「高島屋でミューラーにぶつかりました。」 means you physically bumped against him. No other meanings. Hope neither of you got hurt.

Thanks for the detailed explanation, masaegu.

By the way, I would like to know if it is possible to say 「高島屋でミューラーにばったり会いました。」?

Yes but that would express less of a sense of surprise.

What is the difference between "駅で友達とばったり会う" and "駅で友達にばったり会う"?

The difference is that the first one is "less than correct" and the second one completely correct and natural.

Even though some native speakers make the same mistake as you did, you cannot say 「友達と会う」 unless the meet-up was planned.

I almost posted like this:

I think there isn't any difference between the two sentences.

After reading masaegu's post above however, I am embarrassed at what I might had posted .
Masaeguさん, your post makes a lot of sense, Japanese is my mother tongue though.
Your contribution to this thread is not only useful for Japanese learners but also for English learners like me (even as to Japanese, again which is my native languege as well as English).