Yeah, I would say at least a Canon 430EX. Easily affordable and usable. At least you can upgrade to 580EX in the future and then use the 430EX as a slave. A lot of people follow this upgrade path.

But if you are willing to invest, then 580EX straight.

you very good la. much teach us how to smile when in pain.

viperleong i got already leh. 400D+Sigma 18-200mm OS +50mm f1.8+BG-E3 ._.

waiting for my brother paycheck then ask him buy me flashgun

Depends on what lens you already have and what areas you want to explore in photography.

Budget telelens for decent macro + wild life = Siggy 70-300mm f4-5.6 Macro
Good + Sharp portrait + wide angle lens = Tamron 17-50mm f2.8

this guys sell at RM1.3k only
or
u can buy at shashinki at RM1350 with free shipping

Don't forget about the Sigma 18-200mm APO lens. This one lets you do both at an affordable price. But if you can afford it, the OS variant is good too. Tamron's 70-300 is also not bad.

Yup. 18-200 OS is recommended but I mentioned the non-OS just in case requestor is on budget. The EF70-300mm IS is of course a good lens. I tried it before, the IS is very useful but I opt for the 70-200 F4L in the end. I think Tamron 17-50 + Sigma 70-300 is a good combination. But you can't use the sigma for low light though. I think should be alright if you confine it for daylight shooting.

Should be ok lor with a flash. What is the smallest aperture for that lens? Anyway you'll have problem if you shoot and flash from afar. Either the flash is overworked or your flash will be too harsh because you will most likely spray straight. I'm still not good at this area.

Siggy is better than Tammy for the 70-300mm f4-5.6 Macro lens

I think Sigma is more consistent lar. Try to get APO version if available. F5.6 should still be ok if you have a strong flash like 580EX II. For long distances, you need more than one flash liao. In a hall, you can station 2 large softboxes at the corners. Should give you enough lighting. I saw this implementation from Planet Neil. Not bad the results.