elmie7072 wrote:And how can you figure out how to do the same with other places and names?
Is there a rule to this?
Basically you forget about the way a name is spelt, concentrate on how it's pronounced and try to reproduce the same pronunciation as close as you can using Japanese syllables.
Japanese syllables don't end with a consonant but you can get quite close to the required sound by using syllables from the 'u' row (such as 
ku, 
mu, 
bu, 
pu, 
ru etc) because the 'u' sounds have the most de-voiced vowels. If you need a T or D sound you can't use 
tu and 
du because they're pronounced 
tsu and 
dzu, so you have to use 
to and 
do instead.
L and R sounds are both done using the 
ra-ri-ru-re-ro sounds.
There is no SI in Japanese, but 
shi is close enough for most purposes.
TH is usually done using 
su. V sounds are usually done using the 
ba-bi-bu-be-bo sounds. There is a katakana compound that represents the V sound but since Japanese doesn't have a V sound it's difficult for Japanese speakers to pronounce so I think it's maybe more polite to choose something that's going to be easier to pronounce.
It sometimes helps to use a double consonant where a name has a 'hard' consonant, like, for example, the 'd' and 't' sounds in 'Brad Pitt'. And you need to decide whether or not a long vowel sound improves the pronunciation: for example, 
piitaa sounds much more like 'Peter' than 
pita does (
pita sounds like 'pitter').
Finally, although you can theoretically choose how you spell your name, there is often a well-established spelling for many foreign names and it's probably wiser to stick with that if it applies to you. And like any other language, Japanese already has names for all the countries, so you just have to find out what the Japanese name for your country is.
My qeustion now is how would my name and where I am from be pronounced:
Elmie van Niekerk
I am from Pretoria, South Africa
Pretoria breaks easily into p-re-to-ri-a, and we only need to substitute 'pu' for 'p', giving us 
pu-re-to-ri-a, or プレトリア in katakana. We can check if this is correct by consulting 
Wikipedia Japan (looks like it is).
I'm not sure how your name is actually pronounced, but to me it looks like I would pronounce it el-mee van-nee-kur-k. For Japanese syllables I'd go for 
e-ru-mi-i ba-n-ni-i-ka-a-ku, which is エルミー・バンニーカーク.
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